@mbnoimi May be you should search on github. Personally I feel that there would be very few Qt Widgets based android applications as the best choice would be to use QML and related stuff for mobile platforms.
@p3c0 I really hesitate about QML as I mentioned in this post (I couldn't find it on this forums because of lame search engine so I used google instead)
@mbnoimi Ok. Regarding the searching, if you want to find open source projects better to check it on source code collaboration sites like Github, SourceForge or BitBucket etc.. directly.