The current Android App looks like it was written 10 years ago. It totally ignores Android Material Design Guidelines.
The competition: Dropbox, Google Drive, OneDrive all make use of Material Design and look right at home on Android. They are clean, fast and easy to use.
There's currently an iPrint app in beta testing that has a brand new interface and it looks perfect and really modern on Android.
Filr should be given a Material Design refresh.