In the saddest news of this morning, Steve Jobs is taking another medical leave of absence from Apple: Jobs didn’t specify how long he would be away, except to say that he would continue in his chief executive role and stay involved in major strategic decisions. Chief operating officer Tim Cooks steps in to fill in his day-to-day responsibilities. While U.S. indexes are closed today, trading in Germany shows Apple shares are off 6.4 percent.

At least 60 apps have been downloaded per iOS device and Apple has paid out $2 billion to developers: With Apple close to announcing 10 billion app downloads, Horace Dediu at Asymco runs the numbers using estimates of overall iOS device sales. He calculates that at least 60 apps have been downloaded per device and that number seems to be rising linearly. App downloads are about to overtake song downloads — a “watershed” event. Doing some further calculations using the average app price of $0.29 and the developer’s take of 70 percent, he figures that Apple has paid $2 billion in developers since the inception of the store.

How Amazon’s new SDKs may fuel the development of mobile cloud computing: Data Center Knowledge covers how a couple of SDKs Amazon released last month will make it even easier for mobile developers to access Amazon Web Services, request retries and handle errors.

An eighth grader ousts Angry Birds from its No. 1 spot among free iPhone apps: Fourteen-year-old Robert Nay, an eighth grader in Spanish Fork, Utah, and his mother Kari are the creators of Bubble Ball. It’s been downloaded more than 1.5 million times, pushing smash hit Angry Birds out of the top spot. Nay thinks he might use in-app purchases to help make money from the app.

Piracy might help you too: Developer Daniel Amitay says piracy of his fighting app Punch ‘Em is driving a modest increase in sales, netting him more revenue than if there weren’t any stealing at all.