Catfood TextShips is a simple play by text message version of battleships for Windows Mobile 6 (both smartphone and professional). There is no single player version so you'll need an opponent with a Windows Mobile phone to play. You'll also want an unlimited text message plan as one game could potentially send hundreds of text messages.
Download TextShips
TextShips requires the .NET Compact Framework 2.0 SP2 - if the game won't start on your phone you probably need to download and install this.
After installing if you receive text messages starting with "CFBS" click Menu -> Settings and enable reading your SMS inbox. TextShips tries to intercept text messages automatically but this fails on a some devices. If you need to switch this setting on then I'd recommend exiting TextShips (Menu -> Exit) when you're not actively playing.
I've added a mobile download page at http://www.catfood.net/m - bookmark this on your phone to check for TextShips updates and to download other Windows Mobile products from Catfood Software.
You can get help with Text Ships using by sending me email.