Initially I released my free Android app Movie Quiz only in Google's official Android Market. After a couple of weeks I decided to upload the app to alternative sites/stores/marketplaces as well.

Here's an overview of the number of downloads in the different Android app stores:

Some important remarks:

• Movie quiz was published in the Android Market on September 24th (about 3 months ago) while I only started uploading the app in the other stores late October (about 2 months ago).
• Not all app stores support the same metadata. There are differences in number of screen shots, the size of screenshots, the length of the description field, the length of the changelog field and so on.
• Uploading a new version of the app to all the alternative stores is a pain. It's a tedious process of going through plenty of HTML form to upload new APK files, update descriptions and changelogs.
• Personally I have never used any of the clients of the alternative app stores so I can't comment on their usability.

Is it worth it?

Yes. Without a lot of effort - I didn't spend too much time making screenshots and description texts for each app store - I got an 25% increase in downloads from the alternative app stores.