I really like the programming flexibility of this app. It makes the app very useful.
I also like the fact that it works with whatever music app I choose to use. But I would like a volume control for the voice prompts from the app to adjust the volume level with respect to the music as the prompts are a bit too loud when the music is at my preferred volume.
JD-2 about Intervals Pro: HIIT Timer, v2.2.0