Mobile analytics company Medialets is reporting that the Palm Pre's app store, the App Catalog, has reached 1 million downloads. The milestone comes 18 days after the launch of the handset.

On launch day, the Pre sold 50,000 devices, and the App Catalog experienced 100,000 downloads. 18 days later, the userbase has risen to 150,000, and the total downloads has hit 1 million.

When the Apple App Store was released, the 1-million mark was hit within 24 hours, but there were 16x more apps available and 26x more devices connecting to it.

Comparing at the 1-million mark, though, the average Pre user is 26x more likely to have installed an app and the average app has 16x more downloads in the App Catalog. That might be because, at the time of writing, there are only 30 available.