Palm took another big step toward offering a wider swath of mobile applications for the Pre and webOS. Starting today, it has officially thrown open the doors to developers of paid applications. Consumers, break out the plastic!Here are the details. Starting today, developers may begin submitting paid applications for Palm's e-commerce beta program. Those developers who are already participating in the program will get first dibs at prime placement in the next update to the Apps Catalog come September 15.

There are some rules. Developers can submit either pair or free apps with the following in mind:

• You can charge a one-time fee for the download of your application.
• Initially, the user base for e-commerce will be limited to the United States.
• Developers will receive 70 percent of revenues generated through application sales (less applicable sales taxes).
• webOS users will pay for their application purchases using credit cards and will download apps directly to their webOS device.

This is good news. Palm needs to bulk up the Apps Catalog in the hurry, and this recent development is sure to help. One thing that the Apps Catalog has not offered so far is the opportunity for developers to charge for their applications. That has limited the number of applications initially available for the Palm Pre and webOS. It hasn't helped that Palm has been slow to roll out the official SDK for webOS, which is necessary if developers want to be able to create for the new mobile platform from Palm.

Palm has listed other criteria that are pretty interesting. Check this out:

• Apps should be useful and engaging to users.
• They need to have an appealing design and user interface aligned with Palm UI guidelines.
• They are written specifically for webOS and not delivered through the browser.
• They leverage webOS platform and device capabilities, for example, notifications, multitasking/background processing, location services, accelerometer.
• They have acceptable performance and response time on the device; apps with slow UI response or sluggish performance will be rejected. Applications that consume excessive power on the device will also be rejected.

I like that Palm asks that applications be "useful and engaging". Does that mean fart applications won't be approved? Those apps may be engaging, but I'd say calling them useful is a bit of a stretch. The key criteria above, however, is that Palm demands the apps have solid performance. No one wants slow apps.