Tibetan Synth's has two parts, an android application and a standalone pluginhost written in JUCE. It allows you to play MIDI instruments by humming melodies into your phone's microphone.
In order to compile the Android application, you need Fraunhofer IDMT's libpitch_detection.idmt.so which needs to be placed into the libs/armeabi-v7a folder of the android app. It can be downloaded from here: http://www.idmt.fraunhofer.de/en/business_units/m2d/musicbricks/terms.html