If you have an app in the Android Market of which you want to have both a free version and a paid version, there are basically two ways of doing so. I will describe these two ways in this post. (Disclaimer: This is something that I haven’t tested yet myself, and I’m actually writing this to make sure I won’t forget it myself. On top of that, I don’t know whether there are any other/better ways of doing what I will describe below.)

Two completely separate apps

You can put two completely separate applications in the Market, with the free version covering a subset of the functionality of the paid version. While this is done quite often, this introduces a couple of minor problems:

• If people are satisfied with the free version and want to purchase the paid version, they have to uninstall the free version first and then purchase and install the paid version. If they don’t, they might run into errors (depending on your application and to what extent you messed up your code). You have two separate applications with split download counts in your Developer Console, even though they’re in fact the same application.
• You have to take measures for your development environment to be able to build two different versions of your application with little effort. For quite a lot of people, that can be a bit cumbersome.

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