The guitar for blackberry playbook was a personal project for the Blackberry Playbook.
You use this application to keep your guitar in tune to various tunings (or custom tunings) and have an extensive chord library with all variations of how to play on your guitar with audio to show you how each note sounds in the chord.
The application went live when the playbook went on sale. Which was scary as no-one knew how the application would perform as we all had simulators and not actual devices.
The application received really good press in the playbook community, and got into the top 15 playbook apps ever.