Hi there and thanks for your question!
There is no support for pressure sensitivity in MIDI Designer. Historically speaking, there were several ways to do this:
- Using accelerometer data to guess on pressure: this approach is difficult to implement well. Garage Band used (still uses?) this feature and users find this pretty impressive. Downside is it's difficult to implement and might not work depending on where your device is situated.
- Using size-of-press... there was a lot of news about this back in 2013. Fascinating read about Orphion.
- Using Force Touch
- We asked the Lead Developer of Mito Synth about experiences with Force Touch, and he said: Force Touch is pretty good. Because it’s only on phones right now, it’s hard to make a comparison with a proper hardware keyboard. It’s definitely not like the accelerometer-based hacks popular around the time of the first iOS GarageBand, or the contact-patch-size ones either. It’s nice, smooth, accurate pressure data. One thing to be aware of is that it’s still not “velocity": it’s typically still zero (or nearly zero) at the moment of note-down, as the finger makes contact but hasn’t yet really applied pressure.
So that's quite good, but it's not pressure, per se.
- Another issue is that there's no 3D Touch for the iPad Pro (maybe)
So... for now we don't have any support for Pressure Sensitivity, but we'll keep monitoring the situation and consider the suggestion.