Even if you have big dreams for your clothing shop, it's much simpler to set it up as an LLC and switch to a C corporation when you get closer to ringing the bell on the New York Stock Exchange.
If you can tell from what your app needs to do that you will need to go native, bite the bullet and learn one of the native tongues (Objective C for iOS or Java for Android.) Bell strongly advises that if you go the mobile route, pick iOS or Android and build for that first.
At the same time, C forged its own way in the world, moving from Bell Labs to the world's universities and to Microsoft, the breakout software company of the 1980s.