Apple is making a pre-release version of its iPhone software development kit (SDK) available to a small pool of hand-picked developers, a report claims.

A rough version of the software, which also builds applications for use on an iPod touch, is being made available now, according to Electronista.

While kit contents aren't known, the report claims it produces native applications and that it "somewhat resembles" Google's OpenSocial.

"The SDK will not be the same as writing a Mac OS X application and has its clear limits, people familiar with the matter say," according to the report, noting that "at least one" major social networking site is interested in the capabilities of a native implementation of their service.

Speaking to Fortune, Apple's VP worldwide iPod product marketing Greg Joswiak recently said: "I think the software development kit (SDK) that's going to be available for the iPhone is very interesting, because we think that with the revolutionary multi-touch interface and the phenomenal product that the iPhone is, and certainly having OS X underneath it, that it's going to be an unbelievable platform for developers," he said.

"Of course what we want to make sure we've done is keep the phone safe and reliable, and that's why it's taken us a little while to get this SDK out. Especially now that we'll have a real SDK which means legitimate developers are going to come into the space."