I use Cryptomator to store my personal photos and work images on the cloud, but the phone app is useless without a gallery view. It’s impossible to find a photo on a folder with 1000+ images using the phone, since all we get is a long list of files without a thumbnail. Even on iOS this is problematic, because the thumbnail will only show after downloading the picture.
Also, this feature would be useful not only for pictures but documents too. It’s way easier to find a book or a presentation by looking at the thumbnail than browsing at a cramped filename view.
Please, a thumbnail feature for mobile is a must have.