The Royal Conservatory has a series of theory apps available on iOS that correlate to their Celebrate Theory books. Thus far, there are five apps available: Prep, 1, 2, 3, and 4. (Luckily, while these apps correlate to the RCM program, you do not necessarily have to use the theory books to use the apps!)
[To use this app for music labs, you will need to purchase the all-access pass ($6.99).]
Like many apps out there, students cannot sign in to track their progress, so progress is tracked by filling out this music lab assignment sheet.
This is a BUNDLE download that includes all five levels: Prep, Level 1, Level 2, Level 3, and Level 4.
Each download includes two to three lab pages. You can purchase each level separately or as a bundle.