AOL is expanding its developer program for the AIM instant messaging network.

AOL is adding Mac OS X and Linux developer tools in addition to its existing Windows tools. AOL is also adding support for the Java programming language and the Pocket PC mobile platform.

The company has added new tools for providing PC-to-PC voice communications, creating IM robots and detecting users' geographic location, the Dulles, Virginia, company will announce Monday.

AOL launched the Open AIM program in March to let external developers craft AIM plug-ins, create AIM user interface applications and integrate AIM presence information into sites. So far, about 45,000 developers have registered.

Work together for all

"We know we don't have all the best ideas so we want to encourage the developer community to build their applications on top of our platform. That benefits us, the developers and to the whole AIM community," said Alan Keister, AOL's senior director of engineering for IM and social networking.

Letting third-party developers integrate applications and plug-ins with existing online networks and sites has become popular in recent years. This is often called a 'mash-up' and it is a core characteristic of the so-called Web 2.0 era. It has become particularly common for providers of online mapping services, such as Google and Yahoo, to give developers access to their architecture and let them extend their mapping sites' functionality.

There is no cost for joining the Open AIM program, building applications and profiting from them. If an AIM-based application becomes extremely popular and users log-in to the network more than 2 million times per month, AOL may seek to establish a more formal licensing relationship with the developer, an AOL spokeswoman said.

Extend the scheme

With this program, AIM will have many more applications built for it than AOL could build by itself, said Jupiter Research analyst Joe Wilcox. This is important as competition in the IM space increases and providers fight for market share, he said.

The areas AOL is extending the program into are good choices, he said. IM robots, which provide information on demand via IM sessions, are efficient vehicles for users to obtain data. Location-based services are a natural fit for IM networks, particularly in a mobile setting, to target content at users based on where they are. Finally, the PC-to-PC calling feature is an attempt by AOL to attract internet telephony traffic away from eBay's Skype. "It's a nice extension of what they started several months ago," Wilcox said.