Kangyu, El Amir, thanks a lot for your offer to contribute here!
But the app does not rely on user uploads. Magnuslu gets the data from an online source - SoccerDB. Data on SoccerDB is uploaded by the online community. You may, but dont have to upload results there...A feature to upload from the app is planned by Magnuslu.

(for further details on data source(s) see discussions in this thread)