Trello mobile app functionality and sync issues can often be resolved through systematic troubleshooting steps tailored to your device (iOS or Android) and specific symptoms. The most common problems involve unsynced changes, delayed updates between devices, or cards not appearing across platforms. Solutions typically start with basic app restarts and progress to cache clearing, account reauthentication, or reinstallation, depending on the severity. For persistent issues, diagnostic reports and community support channels provide additional help, while third-party integrations (like TeamGantt or Unito) may require separate sync configurations.

Key findings from available sources:

• Unsent changes are a critical first check—never clear cache or reinstall if changes are pending ^[1]
• Force-sync methods include closing/reopening the app or pulling down on the main screen (iOS) ^[2]
• Android-specific fixes prioritize enabling offline sync, cache clearing, and app updates ^[4]
• Third-party sync tools (TeamGantt, Unito) require manual task duplication or Power-Up configurations ^[5][9]

Troubleshooting Trello Mobile App Sync Issues

Basic Sync and Functionality Fixes

Start with universal steps applicable to both iOS and Android before diving into platform-specific solutions. The Atlassian Support guide emphasizes verifying unsent changes as the first diagnostic step, as clearing cache or reinstalling the app while changes are pending can permanently lose data ^[1]. Users should navigate to their account tab or check for sync indicators (e.g., a spinning icon or "Sync Queue" notification) before proceeding. If unsent changes exist, the priority is to restore network connectivity—switching between Wi-Fi and mobile data often resolves stalled syncs ^[1].

For general app malfunctions, the recommended sequence is:

• Close and reopen the app: On iOS, double-click the home button and swipe up on Trello; on Android, use the app switcher to force-close ^[1].
• Log out and back in: This refreshes the authentication token, which may expire silently. Navigate to *Settings > Account > Log Out* and relogin ^[1].
• Check for updates: Outdated app versions frequently cause sync failures. Update via the App Store (iOS) or Google Play (Android) ^[4].
• Restart the device: A full device reboot clears temporary system glitches affecting Trello’s background processes.

If issues persist after these steps, users should proceed to platform-specific fixes. For example, iOS users report that pulling down on the main board screen (similar to a "pull-to-refresh" gesture) sometimes forces a sync when automatic updates fail ^[2]. Android users, meanwhile, should prioritize enabling offline sync in Trello’s settings to ensure changes queue properly during connectivity drops ^[4].

Platform-Specific Solutions

iOS Troubleshooting

iOS sync issues often stem from background app refresh restrictions or corrupted local data. The Atlassian Support guide highlights that iOS users should first verify Background App Refresh is enabled for Trello in *Settings > General > Background App Refresh* ^[1]. If sync remains stalled:

• Clear the app cache: Go to *Settings > Trello > Clear Cache*. Note: Only do this after confirming no unsent changes exist ^[1].
• Reinstall the app: Delete Trello, restart the device, and reinstall from the App Store. This resolves deeper corruption but requires re-login ^[1].
• Diagnostic reports: For unresolved issues, submit a report via *Settings > Help > Send Diagnostic Report* to Atlassian Support, including details like device model, iOS version, and steps to reproduce the problem ^[1].

Reddit threads confirm that closing the app completely (not just backgrounding it) is the most reliable workaround for sync delays, though users note this is "a bummer" for frequent use ^[2]. Teams experiencing shared sync problems (e.g., new cards not appearing for multiple iOS users) should check if the issue is isolated to one board or organization-wide, as this may indicate a backend Trello server issue requiring Atlassian’s intervention ^[6].

Android Troubleshooting

Android’s open ecosystem introduces additional variables like aggressive battery optimization or conflicting app permissions. The MakeUseOf guide outlines a structured approach:

1. Enable Offline Sync: Navigate to *Trello Settings > Offline Mode* and toggle it on. This ensures changes are queued during offline periods and synced upon reconnection ^[4].
2. Clear app cache and data: Go to *Settings > Apps > Trello > Storage > Clear Cache. If the issue persists, select Clear Data* (warning: this logs you out and removes local preferences) ^[4].
3. Disable battery optimization: Add Trello to the "unoptimized" list in *Settings > Battery > Battery Optimization* to prevent the OS from killing sync processes ^[4].
4. Reinstall the app: Uninstall Trello, restart the device, and reinstall from Google Play. This is particularly effective if the app crashes on launch or sync indicators spin indefinitely ^[4].

Android users should also verify that Google Play Services is up to date, as Trello relies on it for push notifications and background sync. If cards still fail to appear, check if the issue affects all boards or just one—corrupted board data may require archiving and recreating the board via the web app.

Third-Party Integration Sync Issues

Trello’s Power-Ups and integrations (e.g., TeamGantt, Unito) introduce additional sync layers that require separate troubleshooting. The TeamGantt Support guide notes that existing tasks do not sync automatically—users must duplicate tasks in TeamGantt to push them to Trello ^[5]. Common pitfalls include:

• Invalid authorization tokens: If sync errors mention "authorization," log out of the Power-Up and reconnect your Trello account ^[5].
• Manual sync triggers: For TeamGantt, disable auto-sync in the Power-Up settings and manually sync cards by selecting Sync Now ^[10].
• Card visibility rules: Cards may not appear if they’re filtered out by list or label settings in the integrated tool. Verify filters in both Trello and the third-party app ^[5].

Unito’s integration guide emphasizes planning your sync strategy upfront. For example:

• Use a hub board to centralize cards from multiple Trello boards before syncing to other tools ^[9].
• Avoid syncing entire boards if only specific lists or labels are needed—apply filters to reduce clutter ^[9].
• Archive cards in the source tool (e.g., Asana) to remove them from Trello syncs, rather than deleting them ^[9].

For persistent third-party sync issues, contact the integration’s support team with:

• Screenshots of error messages.
• Steps to reproduce the problem.
• The exact time the issue occurred (for server log checks).