Android developers are becoming increasingly frustrated with Google's lack of an updated public software development kit, and many may consider moving on to other platforms.

The issue became more heated after developers learned that Google had secretly been making updated SDKs available to Android Developer Challenge finalists. This came to light this week when Google meant to send notification of an updated SDK to a select group, but accidentally notified the public Android mailing list.

Most of the developer community had been using an Android SDK that was last updated in February, but 50 contest finalists were provided an updated build under a non-disclosure agreement. While other open-source software like Red Hat have been wrapped with non-disclosure agreements, many developers thought Google was aiming to build an equal-opportunity platform.

"I don't think the biggest issue here is who has and doesn't have access to the SDK," said developer Ken Adair in an Android discussion list. "I think the main issue here is communication or lack thereof. Google embraced the development community and touted how they were going to build this platform with the help of the development community. Somewhere along the line, this 'seemed' to change."

After months of speculation that Google was going to build its own phone, last November the search giant unveiled its Linux-based Android operating system to pry open the telecom industry and merge it with the Internet.

But the mobile application market has become increasingly competitive with the success of the Apple App Store, and an open-sourced Symbian operating system is expected to offer many of the same advantages that Android was touting.

"I believe many developers are losing interest in Android," read a message from a user named "jalopy" on the Android discussion forum. "I am currently having a good time developing applications for the iPhone and iPod Touch."