we published a quick fix for Testdroid Recorder 3.1, where we have updated the robotium library.
The 3.5 version of robotium used NumberPicker class, which is not supported in android version below 2.2. We reported this issue and robotium team fixed it fast with new release 3.5.1. Thanks for the very fast turnaround Renas!
You can update to the latest version directly from Eclipse (About Eclipse -> Installation Details, selecting Testdroid Recorder and clicking Update) or use below button (if you have Eclipse Marketplace Client in your Eclipse IDE):