So, what gives? Is there something especially hard about optimizing an Android 2.x (Froyo, Gingerbread) app for Android 3.x (Honeycomb)? Are developers waiting for (presumably, to be called Android 4.0), which will merge the tablet OS and phone OS into one? Is there just not enough demand? Are there problems with tablet app discovery in the Android Market? Is it just because Honeycomb is so new?

We delved into the mystery, reaching out to a number of prominent Android developers for the answers to these questions and more. In our quest for answers, we sought out primarily developers who have successful Android apps that are also available for the iPad, but don't yet have a Honeycomb version. And while we uncovered several significant reasons, virtually everyone agreed on the main underlying cause.

Honeycomb is optimized for a large, horizontal display--large, as in 8.9 inches or greater. (This is why you still don't see 7-inch Honeycomb tablets, though the expected will fix that.) But with the larger display comes design challenges.

"It's much more a design problem than an SDK [software developer kit] problem," according to Bill O'Donnell, the chief architect at Kayak Mobile. "Or rather, it's not a problem, it's just work. You want to use your design resources where they get the absolute biggest return possible." He noted that an app for a 10-inch screen is (or, at least, should be) a totally different experience from an app for a 3.5-inch screen. This is particularly true when an app is primarily focused on text, like Kayak's.