Assalamu alaikum
  1. Please add urdu translation and make it 1 app where you can switch between English,urdu,Bangla,Arabic and whatever other language
  2. Also can you please put something to show which ones are not from Hisnul Muslim
Maybe a symbol in the dua page and next to the dua name in "All Duas"
  1. Sheikh Assimalhakeem has a playlist on fortress of the Muslim. If you divide watching the videos between your team then you can add "Greentech Apps notes from Assimalhakeem's playlist" and state that Shaykh Assim said that Shaykh Albani graded this dua to be weak, or only to be recited in the morning, etc, in the different languages above
And also put a link to the playlist on his channel (as it has better thumbnails than hudatv's one) so people can learn
Sorry for the long post, I just put many ideas here.