What do you look for in a life counter app?

So after enough conversations of "we could make one of these with the features we want" and "why doesnt this app have x feature"; I've decided to try my hand at making a life counter app to see how hard it really is.

I figure if I'm going to do this I might as well see if there is anything that other people dont like about other apps and see if any of them are reasonable to implement.

Current intended feature list is as follows.

• Multi-colour backgrounds to match your deck
• Record of changes to totals
• 2 &4 player mode.
• extra counters for energy, or commander dammage, etc.
• something for deciding who goes first

Anything else anyone looks for in one of these ?

Also this will be android only for now.