This app is a must for all bass students, performers, teachers, school orchestra directors and musicians in general. The directions are detailed and clear and will help students to get a solid foundation. This app will help orchestra directors who do not play the bass get a more complete understanding of bass technique and fingerings which will improve the progress of their students. All advanced students, as well as professional musicians, bassists, string musicians and others, will benefit, for example, from the sections on tone production, practicing, auditioning, etc. I highly recommend this outstanding app.