FretWorx

You can learn to use FretWorx™ in just a few minutes and replace dozens of chord and scale books with a faster, easier, and more powerful alternative. FretWorx™ provides a dictionary of chord, scale, and arpeggio definitions, and an encyclopedia of chord, scale, and arpeggio fingerings.

Use FretWorx™ for multiple instruments and multiple tunings. Multiple instruments include guitar, bass, and many more.

A free, ad supported, version is available with your choice of instrument. Use it as long as you like or use In-App Purchasing to select other instruments, tunings, modules, or ad-free functionality.