I have another suggestion, maybe a fix: when I create a collection in the app but delete it later outside of the desktop app, it remains in the app on my library page for a while, and if I accidentally click into the no-longer-existent collection, it returns a big fat error and makes me feel stupid for having clicked it. If that could be fixed, then the app would be perfect. Also please add the features that MS Annotation X requested.
Furthermore, why isn't there an official iOS/Android Itch.io app? I'd really rather not use third-party apps for popular sites (can't trust them), and it's about time Itch.io got its own Android app, in the very least!