1. The echo (reverb effect) is extremely annoying and becomes stressful to the ear after a few seconds of listening.
2. I'm not sure who is the chanter, but if the the purpose of this app. Is to help people learn, it's better to stick to a steady beat and avoid all these extra trills and ornamentations (hazzat). Simplify the hymns, keep a steady pulse, and plan ahead when you are supposed to breathe, so that you will have compete sentences or phrases without interruptions.
3. I haven't seen a single update or addition since I purchased the app. !