Well, carriers' policy regarding apps in US held mobile market back for years comparing with Europe. For example, here in Russia once there was enormous number of free and paid J2ME apps (usually paid by sending sms to short number). My friends at university read ebooks on <a href="http://en.wikipedia.org/wiki/Siemens_S55>Siemens S55</a> (I used Palm). I know of several companies that were started at this market and later moved to Win Mobile/Android/iPhone etc.