The accuracy is a trade-off between latency and precision. The touch event arrives as soon as you touch the screen, but the actual force of your touch still needs a few milliseconds to actually put the device into motion. Waiting a little bit while collecting measurements gives you quite an accurate indication of the force used, but the increased latency makes it harder to play.
Sliders and knobs will be added in a future version. I wanted to put an MVP on the app store first before adding additional features.
Sliders and knobs are one thing, but this format really invites the use of XY controllers where sliding a finger in the x-dimension modulates one parameter, while the y-dimension modulates another. I am certain more complex schemes should be possible, especially given the possibilities of multi-touch input. I would love to see something like this included.
I think your app looks nice and clean but I just don't see it making a foothold along with the plethora of midi apps available. The midi velocity seem to be your biggest differentiator from competitors but I'm not sure it's enough to gain traction.
Since it's an MVP you're working on I'm going to give you some insight that will hopefully help you out. I'm a composer who mostly works on film and tv. I'm also a hobbyist programmer so I usually end up making our own apps if needed. In the composer community we mostly use TouchOSC and Lemur but both of those apps haven't been updated recently. Lemur is pretty powerful but requires quite a bit of knowledge for non-tech oriented folks. If you'd be able to create interactive and dynamic midi/osc interface like people do with Lemur but much more user friendly I think you'd have an audience.
Isn't that how all of the older iOS apps like Garage Band did drums and such? Not that it was terribly accurate there either, but I assumed it had gotten better since my last iOS device (an old iPad 2).
Yeah I was wondering about that too. From my brief testing 3d touch senses the pressure after the initial touch. Not sure if it can sense the pressure of a tap. At least I didn't see an option like that in the API. Correct me if I'm wrong.
Sliders and knobs will be added in a future version. I wanted to put an MVP on the app store first before adding additional features.