I have a TI89 emulator on my phone, which I use often. It's a slightly outdated interface in the smartphone era, but for me it's still the most usable for certa

I have a TI89 emulator on my phone, which I use often. It's a slightly outdated interface in the smartphone era, but for me it's still the most usable for certain things, particularly unit conversions, 2- or 3-variable RREF calculations, and small CAS calculations. I can do all those things in python, with more overhead, iff I'm at a computer.