Google and its Open Handset Alliance have released the preliminary software development kit (SDK) for their new mobile platform, Android.
The web giant has also confirmed that the members of the Open Handset Alliance (OHA) have signed a "non-fragmentation agreement", thus answering doubts that have been raised over the level of co-operation at the code level between members. Depending on the details of this agreement, this could stop various implementations of Android being incompatible.
The Linux-based mobile software stack — incorporating everything from the operating system to applications — was announced a week ago. The OHA includes 34 companies, ranging from major manufacturers, such as Motorola and HTC, to operators, such as Sprint and T-Mobile. HTC recently announced that it would have the first Android-based handset on the market in the second half of next year.
To attract developers to Android, Google has launched a $10m (£5m) competition to find applications that can be run on the various handsets that will use the platform.
"We've built some interesting applications for Android, but the best applications are not here yet, and that's because they're going to be written by developers," said Google co-founder Sergey Brin on Monday. "We'd like to reward these developers and recognise them as much as possible."
There will be two phases of the Android Developer Challenge, each of which will involve a total of $5m (£2.4m) in prizes. The first phase will run from 2 January to 3 March, 2008. The top 10 applications in each phase will win $275,000 (£133,000) in funding, with the next 10 earning $100,000 (£48,000) each.
One aspect of Android that has raised concerns has been the nature of its licensing. Although the base of the stack falls under the fully open-source GPL licence, many parts fall under the Apache licence, which allows companies to modify the code into a proprietary form and not have to feed it back into the wider Android community.
The chief technology officer of a rival mobile Linux development firm, Trolltech, told ZDNet.co.uk last week that "the temptation will be to diverge".
"Android is offering free food and, when there's free food, people go to have a look and the risk is limited," said Benoit Schillings. "It would be surprising not to see a whole bunch of companies saying: 'This is interesting'. That doesn't mean that's going to be what they eat every day, and it doesn't mean they'll use the entire solution either. I'm always careful when I see an alliance where everyone joins up."
Similarly, Bill Weinberg, the general manager of another mobile Linux alliance, the LiPS Forum, told ZDNet.co.uk on Friday that "the way the Apache licence governs code, it will be very easy for handset manufacturers and operators and other members to add value, but that doesn't do anything to promote interoperability".
"We'd rather have multiple implementations with a single standard," added Weinberg.
However, a spokesperson for Google told ZDNet.co.uk on Monday that the OHA had foreseen these pitfalls. "All of the partners have signed a non-fragmentation agreement saying they won't modify [the code] in non-compatible ways," said the spokesperson. "That is not to say that a company that is not part of the OHA could not do so."
Google's spokesperson highlighted the historical dangers of working with Java, the programming language that lies at the heart of Android. "One of the current problems with mobile Java development is that Java has fragmented," he said. "Java virtual machines have fragmented, but all the members of the OHA have agreed to use one virtual machine that can run script in Java".
Handset analyst John Delaney, of Ovum, told ZDNet.co.uk on Monday that he wanted to see the terms of the agreement "to see exactly what it stipulates".
"It sounds difficult to specify and to enforce," Delaney said. "Fragmentation is to some extent chicken-and-egg. It is caused by vendors wanting to get a competitive edge, but also by consumer choice. As a developer, you either deal with [the disparate handsets in the market] and produce multiple flavours, as people do with Java, or you concentrate on a specific part of the market."
"That situation isn't going to go away as a result of anything Google has announced," Delaney added. "Fragmentation is partly caused by forces outside of Google's control."
Screenshots of the preliminary Android SDK can be found on the OHA website, and a YouTube video demonstrating Android on some prototype handsets has also been released.