A quiet ticking sound is played every second while the timer is running. A louder ding sound is played and a notification is sent when it's time to stir. A double-ding sound is played and another notification is sent, or the existing one is changed, when the coffee is ready.
Immersion Coffee Timer was created using Kivy and python-for-android.
Just what I needed, simple and decent-looking. And it's written using Python with Kivy :)
Would be nice to have known configurations loaded. Also the timer can only be set in intervals of 30 seconds, a rough limitation for those who are picky. Otherwise, really nice interface.