I’m currently working with a partner to develop an iPhone app. In the beginning we had some discussion about whether or not we should simultaneously develop for Android. My reasons for waiting on that were best explained here by Robert Scoble after talking to Path CEO Dave Morin:
If you look at the market share numbers you know that for every iPhone sold Android sells about three devices. So, Path should be wildly more popular on Android than it is on iPhone. It’s not. In fact only about 30% of its customers are on Android. The rest are using iPhones. You might explain this away by some other factor but I’ve heard this from many many developers, including Starbucks and eBay. iPhone users use more apps. The ecosystem of apps is better on iOS. The profitability of app developers is better on iOS than on Android. On and on.
In short, iPhone users better support their respective developer community. Android users expect more freebies.