Looper developer looking for opinions on some interface questions

[Michael Tyson <michael@atastypixel.com>]

Hi!

I'm the developer of an iPhone (and soon to be iPad) looper app called 
Loopy (loopyapp.com), and working on a rather spectacular overhaul for 
version 2.   The app features 6 tracks which can all be overdubbed, and 
merged with each other, and features loop importing, live tempo scaling 
and 'track twisting' to offset tracks (I just implemented this this 
morning - http://youtu.be/Lys6fs01GAw), a built-in drum sequencer and MIDI 
controller support (e.g. foot pedals) for the iPad version.

So, with introductions out of the way, I was hoping I might get some 
opinions by some folks with looping experience, on some interface 
questions (maybe in return I can offer some free copies to interested 
parties?).

My aim is to make the app accessible to beginners, but to give power users 
more control, via gestures.  Of course, though, the gestures have to be 
easy to make when you're slinging a guitar around in one hand, etc.

So a quick overview of the app: The basic unit in Loopy 2 is the track, a 
circular spinning platter (you can see a screenshot of it at 
loopyapp.com).  It's pretty much what you'd expect - tap to record, tap to 
punch out, and it'll start looping.  Tap to mute/unmute.  Tap the center 
part to punch in/punch out, and it'll overdub (I'm considering changing 
this interaction, so it doesn't get in the way of the mute/unmute function 
- It's still a bit up in the air).  

There's other stuff it does (like drag to another track to merge), but 
that's the main interaction.

This is where I'd love some opinions on some interaction ideas I'm working 
on:  I'm planning support for count-in, as well as auto-punch out on the 
next full loop.

Currently, you punch in and punch out (toggle), by tapping the center of a 
track.

As loopers, what do you think is a reasonable approach to begin count-in, 
and specify an auto-end length?

One option I'm considering is tapping with 2 fingers, anywhere on the 
track, to come in at the start of the next loop.

From there, there are two options: Either auto-punch out at the end of the 
loop (1 loop cycle), or just keep on overdubbing until tapped to finish.  
Is one better than another?

I'm thinking about being able to specify how long you want to record for, 
as well, maybe via successive taps - so, for example, if one tap could 
start at the next loop, and keep recording until you tap to stop, then 
*two* taps tells the app to come in at the next loop, and then record for 
one loop.  If you tap 3 times, then that means come in at the next loop, 
then record for *two* loops, and so on.

What do you think?  Does that work?  Is it viable, in a performance 
environment?

Many thanks!

Michael
A Tasty Pixel