In the past, I have played quite a bit of the game Diplomacy, both face-to-face, by email, and by web. One of the appeals of online games is that you are normally anonymised, which means people don’t bring any baggage to the game about how you stabbed them last time.
It’s been a while since I last played, so when I found someone had written an Android app for it, I was interested. In fact, the guy has written quite a neat and usable interface, backed also by a web interface that can be used on desktop computers and non-Android tablets.
It’s free to use, if you are happy to play just one game at a time. You can play multiple games, but for that there is a modest and not unreasonable charge.
It seems initial games suffer from the usual problem of folk signing up and then not doing anything. But he has implemented rules for abandonment, so the games don’t hang; and also for “reliability”, so after you have played a few games, you will start to be game-matched with other reliable players.
The standard game plays 24 hours per turn, with the option to move faster if everyone commits to their orders early.