Recently I've been looking
Android Auto.
Today, I thought that it might be nice if Aquamail made it to this list:
http://g.co/androidauto .
Following the discussion in another thread, I think the recently added TTS feature would be a good reason why Aquamail would be good for AA.
Kostya, I don't know what is required for getting on that list, but I am sure if you and MobiSystems are interested, they you would be able to figure it out (and see if it is feasible).
I am not using AA myself (my devices are still 4.x, and AA supports only 5.0+), but at some point I will be forced to upgrade, and then I 'd consider using AA.