Sometimes users will encounter inevitable crashes while using an app. It's very likely that you cannot access the the stored files and documents, or your projects when the crashes happen. We sincerely apologize for the inconvenience, and would like to provide an ultimate workaround in this article.
Warnings: Always remember to back up or sync your files before you delete an app!
Before deleting apps from your device, please kindly be aware that once you choose to delete, the files will disappear in the device unless you back up them!
You can either choose to sync your files in cloud services(Dropbox, Google Drive, Kdan Cloud...etc.) or back up the files by connecting to the PC/Mac.
If you wish to back up the files and documents, may we suggest you sync your device with iTunes to drag out and save your files in the PC.
1.Connect your device to your PC/Mac, open iTunes or iFiles.
2.Go to the device page, choose "applications" and search the target app, e.g. PDF Connoisseur (shown in the picture below)
3.Tap on the app icon, you can see all the files and documents your saved in the app.
4.Back up your files.