Simple Timer Software for Android Tablet

I run live action laser tag games and would like to use my box to create interesting live action games. You can see my web site and what I do at [[login to view URL]][1]. I need an Android App for tablets that will create and run these various game scenarios like Domination and Headquarters. These are scenarios pulled from popular console video games like Call of Duty. Most of them have to do with timers and on-screen buttons. If you can do a stop watch style app in Android, you should be fine with this. These are simple apps, like Domination (a King of the Hill style game), where 1 team presses their button and the app turns blue and starts adding points to the blue time. Think of it as a reverse chess timer. The graphics and UI on all these scenarios is very, very simple and will not require much work (big buttons, big timers, text). I will design the UI for each screen in any graphics format you want to make it easy. I have provided a lengthy design document. Please review the attached design document to see specifications. I try to be thorough so you have fewer questions. Please don't be scared of the length, it's just trying to explain all the variables. I will provide the sound files for everything if you tell me what format you need. I can also assist with the screen layouts to avoid confusion if needed. Again, just let me know what file format you would like. The only open question to me is whether we can implement wifi so multiple iterations of the software on multiple linked devices can communicate and act in unison. *I will pay extra if we can implement wifi.* I look forward to your response as to how much additional time this will require.