It’s a great time to be a mobile application start-up, especially if you thrive on competition, pressure, and long stretches of over-caffeinated sleepless nights. You’re going to get them. Apple’s new SDK threatens to usher in an unprecedented era of innovation in the mobile space. Great for consumers, great for business users, great for entrepreneurs, great for anybody except those start-ups who enjoyed the luxury of time, the safety of complexity and the protection offered by walled off mobile platforms.

Google started the ball rolling with their early announcement of Android, forcing RIM to open and Apple and the network operators to start opening up, but it’s Apple SDK release that moves the industry to warp speed. Kleiner Perkins’ $100m iFund provides a little more gas, if needed.

Once upon a time (2007), developing apps for phones  took a long time. Closed platforms, business development deals, network operator compatibility, device dependence meant it took a lot of time and money to bring an app to market, and even more time and money to distribute it widely. It’s not surprising that some of the most popular mobile apps (Twitter, Google SMS) rely on a low common denominator like SMS. For a mobile start-up, it meant that you could go to bed on Monday night and be reasonably certain you weren’t going to be dead on Tuesday.

Well, that’s over. Get ready to go to bed Monday and wake up Tuesday to the launch of a competitor with 15,000 subscribers on their first day. Get ready for Facebook-style application growth, where companies like Slide, Rock You and Zynga catapulted to tens of millions of installs within months. It’s going to be an innovative market, and an incredibly competitive one.

Facebook took less than a year to reach 900 million installs of 20,000
applications, I wonder how long it will take Apple to reach the same number. Kleiner Perkins received more business plans for their $100m iFund in 36 hours  than they expected in a month.

“We bet inside how many plans we would see on the first 30 days…and that number was exceeded within 36 hours,’’ said Murphy.

4/1 UPDATE:RIM is trying…

Bottom line: I’m ditching my Blackberry as soon as a 3G iPhone ships.