The best compilation Supplications, Dua & adkar currently is the Hisn al Muslim
{الَّذِينَ آمَنُوا وَتَطْمَئِنُّ قُلُوبُهُم بِذِكْرِ اللّه أَلَا بِذِكْرِ اللّه تَطْمَئِنُّ القُلُوبُ}
* hisn al muslim * great app with variety of dua'a and azkar to bring all our muslim brothers and sisters closer to Allah.