Here are some of the features in VividTracker:

1.  100% compatible with Protracker modules created on the Amiga (this is the aim at least, and so far all the Protracker modules tested in VividTracker are working properly).
2. Supports AudioCopy 2: Import samples from other apps such as Korg iMS20, Animoog and Propellerhead’s Figure
3. Supports Audiobus 2: VividTracker can send audio to other apps like GarageBand and Cubasis through Audiobus.
4. Comes with a great sample editor, where you can easily set loop points, cut and paste samples, etc.
5. Comes with Dropbox sync folder support, so you can keep your modules in sync between devices.
6. VividTracker has a great feature called AutoChord, in which you can transpose one pattern and track to another pattern and track using the effect 8 command (unused in Protracker). This means you can easily transpose a C-Major pattern into a A-Minor pattern with a simple command.
7. Cut, Copy and Paste rows, tracks or full patterns
8. Load modules from other apps such as Mail or Safari
9. Open modules in other apps from VividTracker, for instance Modizer
10. Email modules directly from VividTracker
11. MIDI in support. You can connect a physical MIDI keyboard to your iPhone or iPad and use it together with VividTracker.
12. Bluetooth keyboard support. You can use a BT keyboard to play notes and move the cursor, just like in Protracker.