Better than choose an architecture and try to build the server side of your app, I suggest you to try to find a mate that helps you and was your cofounder. Just you will probably fail in building the app and keeping it working fine in the near future. One-founder teams are very risky for accelerators and VCs. So, you definitely should trust in a co-founder. Read this: http://venturehacks.com/articles/pick-cofounder