Popular applications such as iFunBox, iTools, iExplorer, iBackupBot and PhoneView were previously able to access the sandbox directory of installed applications. This was useful for quickly obtaining or editing files.
iFunBox recently posted an update on the situation to Facebook:
iOS 8.3 ruined our freedom of controlling data in our installed Apps and Games. Apple blocked access of the entire sandbox directory of every installed App since iOS 8.3. Previously only writing is block in executable directory. Now we totally lost the control of Apps on our own devices. We are investigating the situation. Before there is a solution, iFunbox will fail to open data directory of any App if the device is not jailbroken.
Since discovering the problem, developers have been investigating how Apple is blocking their access and iFunbox has found a partial workaround.
We just figured out a solution to bring the sandbox access back **for those Apps that willing to**. Now sandbox access will only be available for Apps having "UIFileSharingEnabled" key set to true in their info.plist [ iPhoneOSKeys.html ] and the access is restricted to /Documents directory only.
So Apps like comic readers and video player will continue being benefited from the fast content transferring via USB cable. Games with IAP will be better protected by having less attack surface. We will release an update regarding the issue soon after fully testing.
iFunbox v2.95 which uses this partial workaround has been released. All apps with 'iTunes File Sharing' enabled can be opened for sandbox browsing. To access other apps you'll need to be jailbroken.
Macroplant, the developer of iExplorer, notes that it's still investigating the changes in iOS 8.3 but offers a temporary solution of accessing app data via the Backups section.
We are currently investigating how the iOS 8.3 update blocked access to the Apps directory, and we are looking into ways around it. All iDevice transfer utilities seem to be experiencing this exact same blocked access in iOS 8.3, so it's not just a bug with iExplorer or iBrowse. Apple has definitely changed something with the way apps can be accessed in iOS.
In the meantime, as a workaround, to transfer app files from your iPhone or iPad to your computer, you can go to the Backups section instead since iTunes backs up both the Documents and Library subfolders of an app and click on the Backup Explorer section. Then, just find the app in the list of folders (every app will be listed as their bundle ID in a reverse domain format (com.developer.AppName)), and you can simply drag/drop any files to your computer or right-click and choose Export to folder.
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