[image]

App Packages: PC-Phone USB Sync

This page covers fetching, installing, and running the Android and PC versions of this app. For more on what you can do with the app after you start it, see the Usage Overview and GUI Guide. To jump to your platform's downloads and usage notes on this page, click its name here:

Introducing the Packages

All versions of this app are, free, ad-free, and unlimited in functionality. It's available for Android on the Play store, and for PCs as downloads at this website. You'll need the Android version to sync to or from a phone, PC versions to sync between PCs, and both Android and PC versions to sync your between your phone and your PC.

This app's Main-tab actions run code in the open-source Mergeall system, which has been actively developed and regularly used on both PCs and Android for a decade. That said, this app, like all apps, has some version constraints which are called out here. As noted along the way, Mergeall's free GUI and scripts are fallback options on all PCs, should the app's executable prove subpar for your PC usage.

On all platforms, prior to running this app on your valued content:

See the About tab for this app's formal terms of use. The rest of this page covers install steps and usage info for each supported platform, as well as Mergeall alternatives for PCs. To read about your platform, either scroll ahead or click your platform's name in the list above.

Android

Get the app on Google Play

This app's Android version is available on the Play store. This is a free and full app with no strings attached. It does not use advertising of any kind, does not require a subscription, and does not require payments to unlock features.

See also the Android screenshots and video for visuals of many of the following package details.

Usage
Google Play automatically manages installs of the app it hosts. To install, visit the link above on your phone. The installed app shows up as an icon in your apps screen, and is run with a single tap as usual. It also runs in split-screen and popup modes on phones that support these.

Android manages uninstalls; use your phone's normal procedure. Logfiles are retained on uninstalls in your Documents folder, per the Data section ahead. On Androids 10 and later, uninstall dialogs include a toggle that allows you to save the app's storage so that it is restored on reinstall; be sure to enable this if you store content in the app's own storage space (i.e., in APP), or wish to retain app settings also per the Data section ahead.

Phone rooting is not required to use this app on Android; Main-tab actions continue running if you navigate to another app or turn off the screen; and closing the app in Recents terminates both the app and its running action (Back taps do not close either one if an action is running). For more on action run modes, see the GUI Guide and Usage Overview.

Versions
The Android app has been verified to work on all Androids 8 and later, and was built for chip architectures most commonly used on Android devices today. The app is known to work on Android 14 most recently, but is expected to work on later Androids too. Watch this space for news about future Androids, and see also the tip below for a special case on Androids 10 and earlier.
Permissions
When you first run the app on Android, it will prompt you to grant it storage permissions, so it can access your device's shared storage, as well as attached USB (and other) drives. This prompt, and the follow-up system dialog, differ between Androids 8 to 10, and Androids 11 and later; the former ask for general storage permission, and the latter for Android's All Files Access.

Either way, this is a firm requirement on Android, so please follow the prompt's directions. The app cannot process your content without this, and will prompt for storage permission again before each Main-tab action and folder popup if not granted. When granted, this app respects the privacy of your content in full; see the privacy statement both in its About and Help tabs and on this website. There's more on Android storage here and here.

On some phones, you may also need to restart the app immediately after granting these permissions to fully enable access. This is a one-time startup task, and the app will prompt you to do this if needed when storage accesses fail in both Main-tab actions and the folder-chooser popup.

On recent Androids, you will also be asked to permit notifications for Main-tab actions, the first time one is started. This is a feature of the default foreground-service mode for actions, which allows you to easily see when an action finishes; see the services coverage here. As of version 1.2.0, the sequence of steps used to request notification permission varies on Androids 13 and later; see the update.

Data
On Android, your app Config-tab settings are saved in the app's private storage, which is normally retained on app updates. To retain settings if you uninstall and reinstall the app, simply click the uninstall dialog's option to preserve app storage ("Keep...app data") available on Androids 10 and later. Caution: your Config-tab settings may be permanently erased if you run "Clear data" in the app's Storage screen in Settings; please use with care.

Also on Android, logfiles are stored more permanently in your phone's shared-storage Documents folder in a subfolder named for this app, and sync backups are saved in the __bkp__ folder of the sync's TO as on all platforms (background info). For Android storage options in general, see see this.

Tips
Quick access: For convenience, add the app as a shortcut to your home screen by long-tapping it in the apps display. There is no widget because it would be the same as a shortcut, but there are notifications for running actions by default.

Removable drive required: To use this app, you'll attach a removable drive (e.g., microSD or USB SSD or thumb drive) to each device in turn, to serve as a conduit for transferring content and changes. This drive acts much like a cloud, but is much faster and fully private. This app does not work if you instead attach your phone to your PC directly by USB. This is covered in the Play-store intro and app docs and demos, but has caused some confusion. For fuller coverage, please see the Windows MTP tip ahead.

Orientations: This app works in both portrait and landscape phone orientations. Landscape is useful if content is too crowded in portrait, but this app may work better in portrait mode on narrow phones due to landscape's display constraints. This naturally is less of a factor for foldables, tablets, and stylus-enabled phones; on other devices, you can address landscape crunch to some degree by adjusting font size in the Config tab for better fit.

Removables on older Androids: There is a special case for Androids 10 and earlier, which limits the folders that may be used for updates on removable drives. In this app, this impacts SYNCs and COPYs run on these older Androids. See its full coverage here and here. As noted in the second of those links, you should also generally wait until a USB drive mounts before trying to access it to avoid odd but temporary states.

App-storage persistence: As a reminder, content in Android app-specific storage only (labeled APP in the Main-tab's folder choosers) may be erased on both uninstalls and app-data clears. See here and here for details, and use shared storage (PHONE) for on-phone content that's immune to these risks.

Drive mounts: On Android, removable drives are automatically mounted at standard locations made available to this app by Android API calls; no user action is required. If you're using a rooted phone, make sure that any manual mounts use the API's standard locations if you wish to use drives in this app. Support for navigating to other locations from ROOT on such phones is experimental. Folder choosers show all drives in standard locations, named by volume label when available.

Large-screen rotation crops: This app's top-of-screen tabs bar may sometimes not appear if you rotate your phone to landscape (wide) orientation while the large-screen taskbar introduced in Android 12L is open. This reflects a sizing glitch in the underlying GUI which cannot be worked around in the app. It's been seen only on a Samsung Fold4 running Android 13, but may impact other large-screen devices. If you run into this, simply rotate to portrait and back again to restore your tabs bar. You can also avoid this altogether by disabling the Android 12L+ taskbar. More info in News.

Memory Notes
This app's memory (RAM) needs are relatively high-end, largely because its GUI is based on the OpenGL graphics system often used for games. On Android, users have installed it on phones with as little as 1G of memory, but this may be pushing against resource limits, especially if other apps are open when it is run. Unfortunately, there are too many variables for a simple guideline on this front.

What can be said is that this app typically requires 100M-500M by itself, though this is less than many games, and virtual and compressed memory ease constraints on some phones. If in doubt, please vet this app before using it for real data on limited-memory devices. Also note that disabling virtual memory for speed per the next tip reduces memory capacity; use with care if space is tight, else apps may not run at all.

Speed Notes
On Android, throttling is a norm. Android itself, its vendors' add-ons, and even the chipset inside your phone may arbitrarily reduce the speed of specific apps or the device at large. This may be done to save battery power, reduce heat, conserve memory, or prioritize apps per biases. Whatever the goal, this can make this app's speed vary so widely that measurement is nearly pointless.

As an example, this app's Main-tab SHOW comparison action was timed repeatedly on Android 13 for the same 200G folders on USB and shared storage. Among its runs, this action clocked in at anywhere between 40 and 240 seconds—a 6X speed difference for identical work. This variance spans devices, and is too irregular to chalk up in full to filesystem caching (which won't help just after a first mount in any event).

While there's no silver bullet for improving this app's speed on Android, a few general tips are worth noting. If this app seems slow, first try closing open apps to free up resources. Next, try restarting your phone to reset its state, if it's been running a long time. If used, also try disabling USB debugging in Settings, Developer options; toggling this off on one phone was seen to speed USB access during folder comparisons by a factor of four (caveat: this may have been coincidental with other variables, and may not work on all devices).

Though not recommended for low-memory phones, it may also help to disable virtual memory, so that parts of the app's memory are not moved to much slower internal storage. Samsung's RAM Plus, for instance, expands memory by swapping to storage (unlike the in-RAM compression of Z-Ram, listed in Developer options). In One UI 5, you can either disable RAM Plus in full, or exclude specific apps: go to Settings, Battery and device care, Memory, RAM Plus. See the web for similar options on One UI 4 and other phones.

It's also worth noting that this app's syncs, even when throttled, are radically faster than the full content copies they are designed to avoid. In the example above, 40-240 seconds for a 200G sync may seem like a long wait, but the full-copy alternative for the same folder takes an entire hour with fast devices, could run well north of this in some cases, and puts major stress on your drives. Moreover, USB makes all such tasks much faster than they would be if run over networks. Despite Android sloth, this app can make the impractical practical.

Power Notes
Some phones kill apps to save battery power more aggressively than they perhaps should. This app runs its long-running actions as Android foreground services to reduce this risk, and no automatic kills have been seen or reported to date (even for multi-hour runs), but it's impossible to test every phone in use. If an action is ever killed on your phone, please disable battery optimizations for this app in Settings, Apps (or similar). Alternatively, try running actions as threads instead of foreground services, via Config-tab settings.

Disabling battery optimizations may also help avoid temporary power-related app stops on some phones. This app uses Android wake locks during Main-tab actions to keep itself running when the screen turns off for a timeout or power-button press, but Android sleep states are convoluted. See also the related Tech Note.

Windows

Download the app for Windows

This app's Windows version is free. It's available on this website as a zipped self-contained executable, which requires no other software to be installed.

See also the Windows screenshots and video for visuals of many of the following package details. Prior Windows releases are archived here.

Usage
To install, download with the link above, and unzip the downloaded file anywhere on your Windows PC (but not in C:\Program Files, per the tip ahead). This will create a folder named PC-Phone USB Sync, which contains a Windows executable named PC-Phone USB Sync.exe. In Explorer, the .exe part may be hidden, and be sure to fully unzip with right-click/Extract All instead of double-click.

To start the app, run the executable as usual (e.g., by clicking its icon in Explorer). To uninstall, simply delete the executable's folder; logfiles are retained on uninstalls in your Documents folder, per the Data section ahead.

As usual on Windows, Main-tab actions continue running if you navigate to another program, and closing the app's GUI also terminates its running action if you confirm the close. For more on action run modes, see the Usage Overview.

Note that the app's Windows executable will not run without all the other items in its unzip folder—and will warn you and shut down if it detects this case. To move the app elsewhere after unzipping, move the entire folder, not just the executable inside it.

Versions
The Windows executable was built for the Intel 64-bit architecture, and will not work on systems using incompatible chips. In addition, this executable was built on Windows 11 and verified to work on both Windows 10 and Windows 11, but results on older versions of Windows are unvetted and may vary. If you have trouble using it on your PC, please see the Mergeall alternatives below.
Permissions
When you first run the app's executable on Windows, you may be prompted to allow it to run. This is a security check enforced by Defender SmartScreen (if enabled), and is designed to prevent programs from running without your knowledge. To get past this, select More info in the first popup, and then Run anyway in the second; this allows this app to start, and all future launches of it will run without these prompts. The app itself never requests any permissions on Windows, but must be able to save files in its install folder; see the tip ahead.
Data
On Windows, your app Config-tab settings are saved in file settings.pkl in the install folder (the one made when you unzipped the download), and can be saved and restored there if you delete and reinstall the app's folder. Logfiles appear in the Documents folder of your home/account directory C:\Users\yourid, in a subfolder named for this app. As on all platforms, sync backups are saved in the __bkp__ folder of the sync's TO (background info).
Tips
Quick access: For convenience, add the executable as a shortcut on your desktop or pin it to your taskbar or Start menu, using right-clicks and your platform's conventions.

Title-bar colors: To change the color of the app's title bar on Windows, set your Accent color in Settings' Personalization=>Colors. For example, if you use Windows' dark theme, you can apply a darker title-bar color than that shown in some older screenshots by enabling Accent Color's Automatic mode, as well as its option to show on title bars.

Antivirus conflicts: This app accesses content folders to do its work. Make sure that neither your content folders nor this app's install (i.e., unzip) folder or executable are blocked or throttled by your antivirus program (e.g., whitelist the executable if required). Else, over-aggressive antivirus software can impede, and even cause failures in, this and other programs on Windows. Though rare, this is suspected to have caused this app's folder chooser to hang for seconds and fail, though timeouts added in 1.1.0 avoid hangs.

Drive mounts: On Windows, this app looks for storage devices by drive letter (e.g., D:). Removable drives, including SSDs, thumb drives, BDR readers, and most cameras, are automatically mapped to drive letters when attached. To use a network share in the app, be sure to map it to a drive letter per standard Windows procedures; within the app, its letter is automatically translated to a UNC path, per the more-details button here. In all cases, the top of the app's folder chooser lists drives by their volume names, if available.

Network-drive navigation: Due to an unresolvable glitch in the underlying GUI toolkit, the app's folder chooser cannot navigate up to the top of a Windows UNC path. For example, in a mapped network drive's path \\server\share\folder, you can use .. taps to navigate up to the level of folder, but not higher: the .. at this level does nothing. This differs from other storages, but has a simple workaround: to go to a network drive's \\server\share root, simply tap that drive's red storage button (like this) at the top of the chooser's popup. More info.

Browser download warnings: Please ignore the warnings issued by some web browsers when you download this app's zipfile. In particular, the current Chrome on Windows by default displays a warning that this zipfile is "uncommon" and may be "dangerous," and blocks the download. You can easily get past this by clicking the warning's arrow, and can disable the opinionated blocks altogether in Chrome by picking Settings, Privacy and Security, No protection. Zipfiles from disreputable sources can be harmful, but computer systems regularly underrate user discretion.

Windows WSL2 Linux: As of early 2024, Windows users can also run the Linux version of this app in the latest version of Windows Subsystem for Linux, but this works very slowly and poorly today. Most users should instead run the Windows version of the app in Windows, and sync WSL2 content by mapping it to a Windows drive letter. For details, see the Linux note ahead and the full Tech Note.

Where to Install
To install the Windows package, unzip it anywhere on your C: system drive—but not in C:\Program Files, or its Program Files (x86) sibling. Programs don't have permission to write files in those folders by default (whether you're logged in as administrator or not), and this app needs to write admin files in its install folder. Instead, unzip and run in your account's Downloads or Desktop folders; anywhere in your account's folder (a.k.a. C:\Users\yourid); or in C:\anyother, where anyother may be a folder you create in Explorer for this purpose.

You can still install in Program Files folders if you use right-clicks to run the executable as administrator (always) or change its folder's permissions for users in Properties/Security (once), but unzipping to another folder is simpler and more secure. More info on the web. As of Oct-2023, this app now detects unusable install folders, and closes with a tips popup to avoid a startup crash for a failed write; please unzip elsewhere if this popup appears on first run (related post).

Other install-related notes:

MTP Does Not Work
When using this app to sync phones and PCs, you'll attach a removable drive (e.g., a USB thumb drive or SSD) on each device in turn, to serve as a go-between for transferring content. This drive serves a role similar to network drives and clouds, but is faster and more private, and provides an extra local copy. Please see the coverage of this intended and recommended usage here, here, and here, as well its video demo here. You can skip the rest of this tip if that makes sense to you, but user feedback suggests that an extra clarification may be helpful.

Specifically: you cannot sync with this app by connecting the phone to your PC directly with a USB cable. This mode uses the MTP protocol. Because MTP is not a real filesystem mounted to a drive letter, the phone's folders won't appear in the app's folder chooser on your PC. In addition, because MTP is a PC-side view only, it won't let you see your PC from your phone. While you may find tools for Windows that mount MTP to drive letters and translate file operations to the MTP protocol, they will likely be very slow, prone to data corruption, and unable to retain file metadata like timestamps. Some may also present phones as read only.

As an example, a recent MTP test using a popular $50 MTP mounting program for Windows ran an app SHOW action for 25 minutes before dying roughly 10% through the content folder. Moreover, it skipped numerous files, and incorrectly classified almost all files it managed to visit as differing per timestamps. A second try fared no better, running 1.5 hours before the mounting program crashed far short of completion. By contrast, the same test with a USB drive finished in just 40 seconds, and with correct results. No SYNC updates were tested, because MTP mounting is clearly unusable for all but the simplest of tasks. Use a removable drive as intermediary instead, per this app's guides. More info on the web.

Recent Updates
February 21, 2024: The Windows 1.1.0 package was rereleased to incorporate two changes: hangs for inaccessible drives that could occur while navigating in the app's folder chooser have been eliminated, and the timeout for detecting hangs has been shortened to avoid GUI lags (release note).

December 23, 2023: The Windows 1.1.0 package was rereleased to skip unlistable folders during the comparison phase of sync-related actions. This reflects a rare Windows context, but it's crucial that UNDO run even for system-related folders (e.g., to restore a user's home folder). More here.

November 10, 2023: The Windows 1.1.0 package was rereleased to avoid a very rare module-import abort that likely stemmed from Windows Storage Sense wrongly deleting the app's temp folder while the app was still running. See also News.

October 24, 2023: The Windows 1.1.0 package was rereleased to add a run-time check and tips popup for installs in unwritable folders, which formerly caused crashes. This update also recenters the window when first opened to avoid off-screen content. More info: tip ahead and News.

September 19, 2023: The Windows 1.1.0 package was rereleased to avoid overly small windows at startup on high-resolution displays (e.g., 4K), by scaling initial window size to screen density. Please refetch and reinstall on Windows as needed, and see News for more info.

macOS

Download the app for macOS

This app's macOS version is free. It's available on this website as a zipped and self-contained macOS app, which requires no other software to be installed.

See also the macOS screenshots and video for visuals of many of the following package details. Prior macOS releases are archived here.

Usage
To install, download with the link above, and unzip the downloaded file anywhere on your macOS PC. This will create a macOS app named PC-Phone USB Sync.app. To start the app, run it as usual (e.g., by clicking its icon in Finder). To uninstall, simply delete the app; logfiles in your Documents folder and settings in Library are retained on uninstalls, per the Data section ahead.

As usual on macOS, Main-tab actions continue running if you navigate to another program, and closing the app's GUI also terminates its running action if you confirm the close. For more on action run modes, see the Usage Overview.

Note that the app's macOS version is an app bundle created by unzipping. This is really a folder, but must be treated as a whole; the executable inside it won't run without all the other items in the app bundle. Fortunately, macOS makes it difficult not to treat the app as a single item.

Versions
The macOS app was built as a Universal 2 binary, and is known to run natively on macOS computers using both Intel 64-bit architecture chips, and newer Apple silicon M-series ARM chips. Though not required, the Intel version included in the binary can also be run on an installed Rosetta 2 emulator.

In addition, this app was built on macOS Catalina (10.15); it is expected to run on this and newer versions of macOS, but not older (though see the update below). At this writing, this app has been verified to work through Ventura, the most recent macOS. If you have trouble using it on your PC, please see the Mergeall alternatives below.

Update: The macOS app has now been verified to also work on an older Intel-based system running macOS High Sierra (10.13). Hence, the app formally supports macOS machines running High Sierra and later. Earlier versions remain doubtful (an El Capitan device has been seen to issue an incompatibility dialog and prohibit running the app).

Permissions
When you first run the app on macOS, you may be prompted to allow the app to run. This is a security check enforced by Gatekeeper (if enabled), and is designed to prevent programs from running without your knowledge. Approve the app in your Settings or otherwise, as directed by the prompt or its "?" info. You can approve in the dialog itself, but only if you've allowed all apps from independent developers.

This story morphs often, but on recent macOS versions (e.g., Ventura), you can get past the first-run warning by simply selecting Cancel in the popup (instead of Move to Trash); control-clicking the app and selecting Open; and selecting Open in the resulting popup to start the app. All subsequent launches will run without warning popups.

Also on this platform, macOS will ask you to approve removable drives and some folders when they are first accessed by the app, and the app will suggest but not require macOS's Full Disk Access storage permission on the first run only. Drives and folders are required, but Full Disk Access applies only to app and system-level content, and is unnecessary in typical usage; you can opt to turn it on later in Settings if actions fail because of permissions.

Note that you generally do not need to restart the app in full after a permission popup for a drive or folder: simply rerun the last request after handling the popup and dismissing the app's inaccessible message (if one appears). Either way, these popups are normally one-time events.

Data
On macOS, your app Config-tab settings are saved in file settings.pkl in the PC-Phone USB Sync subfolder of /Users/yourid/Library, and are not deleted if you remove and reinstall the app (you may have to unhide this folder to see it in Finder: try shift+command+.). Logfiles appear in the Documents folder of your home directory in a sub folder similarly named for this app. As on all platforms, sync backups are saved in the __bkp__ folder of the sync's TO (background info).
Tips
Quick access: For convenience, drag the unzipped app to your Applications root folder to make it available in Launchpad. You can also add an alias to the app on your desktop or drag it to your Dock, using your platform's conventions.

Drive mounts: On macOS, the app assumes that all external storage is mounted in the /Volumes folder, because this is where removable drives automatically show up, and where network drives mounted in Finder appear. If you mount drives manually on macOS and want them to appear at the top of the app's folder-chooser popup for easy access, be sure they are in this standard folder; the app cannot guess other arbitrary locations. As a fallback, you can always navigate down from the ROOT folder (/) to select and use other drives mounted in atypical places.

Unicode-filename issues: Though rare, if you run across errors and skips for some non-ASCII Unicode filenames on macOS, please see the Tech Note for possible solutions, including a precoded fixer script. This has cropped up only for filenames with Unicode variant characters having more than one representation, and only when such filenames are exported from macOS to Windows and back again on exFAT drives.

Logfile scrolling: When scrolling filenames in the Logs tab with a touchpad, you might find it more accurate to scroll by grab+move than simple swipe. To perform a grab+move, simply press and hold the touchpad while the cursor is over the scroll area, and quickly do an up or down gesture. This may offer more control over the scroll, though this is naturally subjective, and mouse users' mileage will vary.

Linux

Download the app for Linux (Ubuntu 22)

Download the app for Linux (Ubuntu 20)

This app's Linux version is free. It's available on this website as a zipped and self-contained executable, which generally requires no other software to be installed. Because Linux executable usage is convoluted, this site provides the app in the two forms above:

See also the Linux screenshots and video for visuals of many of the following package details. Prior Linux releases are archived here.

Usage
To install, download with one of the links above, and unzip the downloaded file anywhere on your Linux PC. This will create a folder named PC-Phone USB Sync, which contains a Linux executable named PC-Phone USB Sync. To start the app, run the executable as usual (e.g., by clicking its icon in your file explorer or running it from a command line). To uninstall, simply delete the executable's folder; logfiles are retained on uninstalls in your Documents folder, per the Data section ahead.

As usual on Linux, Main-tab actions continue running if you navigate to another program, and closing the app's GUI also terminates its running action if you confirm the close. For more on action run modes, see the Usage Overview.

Note that the app's Linux executable will not run without all the other items in its unzip folder—and will warn you and shut down if it detects this case. To move the app elsewhere after unzipping, move the entire folder, not just the executable inside it.

Versions
The Linux executables were built for the Intel 64-bit architecture, and will not work on systems using incompatible chips. Moreover, these are plain executables built and verified on Ubuntu Linux only (Ubuntu 20 and 22, specifically). Due to the convolutions of Linux distributions and packaging, they cannot be guaranteed to work on every Linux-based computer. If you have trouble using them on your PC, please see the tip and workaround ahead, as well as the Mergeall alternatives below.
Permissions
There are no known permission requirements to use the app on Linux, and no permission requests are issued by the app when it is first run on this platform.
Data
On Linux, your app Config-tab settings are saved in file settings.pkl in the install folder (the one made when you unzipped the download), and can be saved and restored there if you delete and reinstall the app's folder. Logfiles appear in the Documents folder of your home directory (a.k.a. ~) in a subfolder named for this app. As on all platforms, sync backups are saved in the __bkp__ folder of the sync's TO (background info).
Tips
Quick access: For convenience, add the app your Applications screen and quick-access panel using your platform's conventions. To make this easier, the app's unzip includes a file ppus-linux.desktop in its usbsync-pc folder. See this file's top comments for detailed install instructions. In short, you'll edit the file for your user name and paths, add the app to Applications with a desktop-file-install command, and right-click the app to add it to the quick-access panel. The file has URLs for more help. Simpler alternative: in most file explorers, you can make a link to the program's folder, and drag it onto your desktop for fast starts.

Font size: The Linux package's font may be initially small on some devices, especially in the original Ubuntu 20 build. The newer alternative 1.1.0 build for Ubuntu 22 addresses this by increasing the initial font size slightly, but the preset may still be subpar for some users. To improve, simply change the global font size in the Config tab, and tap to save your change; the new size will be used on all later runs. See the Linux screenshots starting here for a demo.

Missing libraries: Due to the choices of the tool used to build this app's Linux executables, it's not impossible that some required libraries may be absent in both the app's package and your Linux install. If the app does not run, check for error messages by launching it from a shell command line, and viewing Kivy logs in ~/.kivy/logs/. If you find reports of missing libraries, try installing these dependencies in your local Linux. See also the general Linux library-skew Note.

Drive mounts: On Linux, this app searches for mounted drives in both /media/user and /mnt. The former is where automatically mounted storage appears, including both USB drives and the dual-boot Windows partition. The latter is sometimes used for manually mounted drives, including network drives, but this is variable, and /media works just as well for user mounts. Really, drives can be mounted nearly anywhere on Linux, but make sure they are in one of these two standard folders if you want them to appear at the top of this app's folder-chooser popup for easy access. As a fallback, you can always navigate down from the ROOT folder (/) to select and use other drives mounted in atypical places.

Update: the February 2024 rerelease of the Linux app now recognizes mounts anywhere in /media (technically, /media*), and not just in the user's subfolder. It also now uses stricter rules to omit non-drive mounts in the folder chooser: the mount source must be /dev (a physical device) or a Windows drive letter (e.g., C:\ in WSL2). The /mnt folder is still also searched for mounts, as this is where WSL2 auto-mounts the Windows system drive and removables, and ROOT is still a fallback if these rules prove to be too conservative. More info here and here.

Usage in Windows WSL2 Linux: As of February 2024, the Linux version of this app is known to work, though just marginally, on the latest release of Windows WSL2 Linux, with an Ubuntu 22 distribution. That platform suffers from substantial glitches and speed issues today, and most users would be best served by syncing WSL2 content within the app's Windows version, by mapping WSL2's storage to a Windows drive letter. Running the app in WSL2 itself, however, offers faster access to native Linux filesystems for those patient enough to overlook its current usability problems. For complete coverage, see the Tech Note.

Libraries Workaround
(Update: The following workaround helps when running the original Ubuntu 20 build on Ubuntu 22, but is not required to run the new Ubuntu 22 build on Ubuntu 22. It may, however, apply when using either build on other Android installs.)

On some Linux installs, you may need to add the following line to your ~/.profile or other startup file, if this app's executable displays its splash screen but does not start in general:

export LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libstdc++.so.6
This is known to make the Ubuntu 20 executable run correctly on Ubuntu 22, and may help on other Linuxes as well. It works around library skew that impacts this program, as well as others that use the same toolset. For more details, please see the Tech Note.
Recent Updates
February 21, 2024: The Linux 1.1.0 package for Ubuntu 22 was rebuilt with changes that make it more usable on the Windows WSL2 platform, and improve drive detection on all Linuxes. See above for more on WSL2 usage, and see the Tech Note for changes included in this release.

December 27, 2023: The Linux 1.1.0 package for Ubuntu 22 was rebuilt to include unlabeled removable drives at the top of the app's folder-chooser popup. Users no longer have to navigate down to these from the ROOT folder. Details.

October 3, 2023: The Linux 1.1.0 package was rebuilt on Ubuntu 22, to avoid the export workaround above on that platform. This build is an alternative to Ubuntu 20's, and also increases initial font/window sizes; see News.

September 19, 2023: The Linux 1.1.0 package was patched and rereleased to avoid overly small windows at startup on high-resolution displays. Please refetch and reinstall on Linux as needed, and see News for more info.

Mergeall Alternatives

Download Mergeall alternatives

While this app has been ported and built to run on most recent PCs, it may not work on some devices whose hardware or software varies from current norms.

If you have trouble running this app on your PC, you can also try using Mergeall's free GUI executable or source code, captured here. This GUI's Report and Update buttons work the same as (and in fact use identical code to) this app's SHOW and SYNC buttons, respectively. They can be used in place of this app to sync content on your Windows, macOS, and Linux PCs, both before and after using this app's Android version on your phone.

Mergeall's GUI app and executables for PCs are platform- and chip-specific too, but its source-code version of its GUI will work broadly on nearly all PC platforms. You can find resources for using both the app/executable and source-code versions of Mergeall's GUI at the download link above.

Mergeall's source-code package also includes command-line scripts that mirror all the actions on the app's Main tab. For example, mergeall.py corresponds to the app's SYNC, SHOW, and UNDO, and diffall.py and cpall.py are DIFF and COPY. These scripts can be used as a last-resort content solution for PCs, though both the app and Mergeall's GUI are naturally more user friendly.

Mergeall's scripts and GUI work on Android too—the former in the Termux app, and the latter in Pydroid 3 with patches—but only on Androids 8 through 10, and with much less convenience than the newer Android app. As of Android 11, USB drives are not accessible to Mergeall's code without a permission that requires a stand-alone app. While this can be partly addressed with multi-step heroics, the results are dependent on other apps, functionally limited, and not in line with Android usage paradigms.

The PC-Phone USB Sync app works around this Android permissions constraint in full, while adding ease of use, enhanced functionality, and a graphical and consistent content-management experience across phones and PCs.

For More Info

That wraps up this guide to the app's packages. For info on using the app after you install it, see the other sections of the User Guide.