I will not be releasing any new versions of leafDrums. However, the code has now be released as open source, so if anyone wants to develop a new version, please do. Full source code and more information.
You can easily put together a drum pattern using sounds from standard .wav or .ogg audio files (a basic set of drum sounds is included). Audio effects like distortion allow you to customise the sounds.
The user interface was designed from scratch to be as simple and clear as possible. Everything you need is directly visible on the two program screens; nothing is hidden in menus or dialogs.