Trying to shake off some programming rust, my goal for the winter break is to improve my mobile application programming skills, or, in other words, creating and selling apps for cell phones. Where to start?First, which platform should I use? Creating apps for the iPhone is my preference, but, as I've ranted about before , Apple requires me to own a Mac (which I don't have). It's obnoxious. Meanwhile, Google's Android doesn't require anything, and that's quite a selling point.Second, looking a few steps down the line, when I eventually want to sell my app, Apple's App Store requires a $100 registration fee, whereas the Android Market only asks for $25. Both companies take a 30% cut from sales, but Apple won't pay you anything until you break the $250 threshold, whereas Google has a $1-earned minimum. Additionally, employees at Apple have to approve all apps before they get posted in the store, and this has been a nightmare for some developers , since Apple often rejects apps without giving any explanation as to why.Third, from a programming perspective, iPhone apps require that they be coded in the language of Objective-C. Meanwhile, Android apps can be coded in either Java, PHP, C/C++, or several other languages. Thus, no need to reinvent the wheel - you can just go with what's already your area of expertise. For a more detailed technical comparison, I recommend reading Green's Opinion All things considered, I'm going with Android.