On iOS you can view the thumbnails of encrypted files if you search for the file names in Siri search. Steps to reproduce:
- Unlock your vault and view images through the Files app (remember the file names of the viewed files).
- Close the Files app and lock your vault using the Cryptomator app.
- At the home screen swipe down to reveal the Siri Search field.
- In the search field type the file name for one of the files you viewed in Step 1.
- The file will appear in the Files section of the search results.
- You cannot open the file from here however if you click the Search in App link next to the Files header the Files app will open and present the thumbnails of the images.
- The images cannot be opened from here but the thumbnails will be visible.