As someone who used to practice to changes by recording them myself, I think this is a great tool. I am the Director of Education for Tokyo School of Music (and guitar instructor as well), and all our guitar students have their own iPad and iRealb is a required download. The only real suggestion I have is more styles. You have obviously dedicated a lot of time and effort to the Jazz section. I would personally like to have better R&B, Soul, Blues, etc.. styles. Before I started using iRealb, I used a Boss Jam Station which has great Blues and R&B styles, some of the same patterns would be great.