One thing we absolutely got correct when starting our company – we started by identifying a pain, and looked to fix it. In particular we realized that email as a collaboration tool was broken, especially for collaborating over documents. We set out to fix that high level pain rather than to find a problem that we could solve with our technical areas of expertise.
“Look to solve pain” is not novel advice to anyone looking to start a company, but still, all too often, you see people trying to think of startup ideas that will leverage their technical expertise. While it obviously doesn’t’ hurt being an iPhone expert if you’re building a mobile company, there’s no reason you need to limit your options to just mobile iPhone apps. Any programmer is capable of ramping up *enough* in an area such as mobile, web, desktop to build out a minimum viable product. You can always bring in help latter once you’ve found product market fit.