I‘ve been using Processing IOS for over a year now and although it‘s the best option if you want to Code Visual stuff on your iPhone, some things don‘t works as they should (like PShape…).
As for wether createFont works, i doubt it…
Mainly because it seems like the IOS Version mainly accounts for practical methods / classes, since space is limited…
But also because i‘ve had some problems with the „new“ file system they added (~1/4year ago, iirc)…
Your best bet with the IOS version is probably to stick to technical things and do „fancy“ stuff on your computer.