a feature to long press a word to open a menu of different taps to show
1) the word meaning in Arabic and chosen translation
2) similar word in other verses (motashabihat)
3)the detailed tajweed rules in this word (as in quran University app ) and to hear it repeatedly with normal or slow mode to be able to correct the tshkil and tajweed
the quran University app has a detailed tajweed rules and options to hide some or show all with color code and even a tutorial videos to teach tajweed but it has a very poor user interface i hope you can provide its features with a better smooth user interface