I'm the developer of the Exoplanet App ( [exoplanet.hanno-rein.de] ). My story is quite different. The "sales" of my app (it's actually a free app) have been much more organic over.

There's an app for that:

There's an iPhone app for that:

Here's a free iPhone app that keeps you up-to-date with all exoplanet discoveries. It has some pretty cool visualisation as well...