Once you delete a file from the Scanner Pro app, it appears in the Trash Bin and stays there for 30 days. After 30 days, the deleted file cannot be restored in Scanner Pro but can be accessed in the cloud storage if you’d linked one to the app.
It’s not possible to restore files in Scanner Pro if it’s been more than 30 days since deletion. However, if you have Auto Upload enabled, you might still access the deleted files in the cloud storage you linked to Scanner Pro. Unfortunately, files from the cloud storage cannot be imported back to Scanner Pro as it hasn’t an import option yet.
If you deleted the app itself and there are no files after you install it again, there might be two reasons:
1) You had iCloud backup enabled, but it takes scans too long to appear back in Scanner Pro. In this case, please refer to this article to fix it.
2) iCloud backup was turned off, which means that files were stored locally and can’t be restored in Scanner Pro in any way. However, if you’d enabled Auto Upload, you may find the scans in the cloud storage you linked to Scanner Pro. While it’s currently not possible to import them back to Scanner Pro, you’ll still be able to access the files.