Google's Android developer kit for mobile phones has been successfully installed on several hardware devices, a step toward turning it into a genuine mobile-phone platform.

The Android Software Developer Kit (SDK), first released in November, has been developed by Google and others as part of the Open Handset Alliance with the goal of spurring innovation in the mobile space. The platform, based on the Linux 2.6 kernel, will comprise an operating system, middleware stack, customizable user interface and applications.

Google released the preview version of Android without support for actual hardware - instead, developers were given a software emulator based on Qemu. However, running the software on actual hardware can give developers a more accurate idea of how their applications will run.

And while the Open Handset Alliance (OHA) has more than 30 corporate members, open source developers are crucial to the project's success. Google released the SDK with a few demonstration applications, and is relying on third parties to come up with the rest.

Some developers have indeed criticized the OHA's hands-off approach, criticizing the lack of support for developers as well as bugs and missing functionality.

Possibly the first hardware platform to run Android was the Armadillo-500 from Atmark-Techno, based on Freescale's i.MX31L mobile processor, according to a blog post, which credited Australian developer Ben Leslie for the initial work.

Japanese telecommunications company Willcom has demonstrated another prototype Android reference board, also running on a Freescale-based chip, according to a Japanese gadget news website.

Fujitsu has published instructions on running Android on one of its reference boards.

Several developers said they had used Leslie's development work to run Android on different versions of Sharp's Linux-based Zaurus handheld computer.

One of these was software development firm EU Edge, which demonstrated Android running on a Zaurus SL-C760.

Another developer used a similar technique to run the platform on a Zaurus SL-C3000.

Installation has become easier via an installable Android image for Zaurus. A developer using the handle "cortez" and running a Zaurus SL-C3100 combined the Android SDK with the Poky Linux kernel, creating an installer that can be booted within a few minutes.

So far the Zaurus implementations have certain limitations - for instance, Android's Bluetooth doesn't yet work with Zaurus, and it can't yet interact with the handheld's touchscreen.

Google hasn't yet announced support for an official hardware development board. The first commercial handsets running Android are expected in the second half of this year.