I just downloaded version 2.0 through the app store and I had set it up to give me notification every 20% of battery, but it doesn't work.
I mostly get the notifications "on the way up", meaning while charging the battery (sometimes they also are missing, for example I have never received a 40% notification even though it's marked), and I don't remember ever getting any notification "on the way down", meaning while the battery is discharging.