Hi Ukemonster. iRealb is the electronic equivalent of what's known as a "fake book". In other words, if you're playing a song you're not familiar with, you can look at a simplified chord chart and "fake it". Professional musicians have been using fake books for generations. Now, in the magical 21st Century, computer apps like iRealb let them store countless charts on their tablets or smart phones, rather than drag a stack of paper to the job.

Among many other functions, iRealb allows you to instantly transpose the chords to a different key if desired. And hitting the "Play" button will simulate a pretty darn good rhythm section if you want to practice a tune in real time. Because of copyright restrictions, it doesn't include lyrics or melodies. And it is definitely not a "karaoke" program that tries to emulate any original recordings.