The executives, who participated in the panel "The Platform Advantage" at the Web 2.0 Summit in San Francisco on Friday, generally agreed that platform providers must have concrete policies and rules for developers to follow.

Other best practices are to offer developers clear ways to generate revenue and to not treat them as rivals when they create applications that compete with those from the platform providers, the panelists said.

"From our standpoint, one of the most important things with our platform is that we have very clear guidelines, very clear rules, and we adhere to them," said Amit Kapur, MySpace's chief operating officer, referring to the company's recently launched application platform for its social-networking site.

Elliot Schrage, Facebook's vice president of communications, public policy and platform marketing, said his company prioritizes transparency in its dealings with developers, particularly regarding changes to the application platform. It's also important to seek and consider feedback provided by developers about the platform, and provide tools and resources, Schrage said.

In addition to clear ground rules and communication, platform providers must display a firm commitment to the platform, which in turn fosters confidence among developers that their investment of time, effort and resources is protected, said David Treadwell, corporate vice president of Microsoft's Live Platform Services.