Since I saw some great OTZ80 software ideas in the hardware section, I've decided to make a new topic here dedicated to software discussion.
Please remember to not bash anyone for their ideas, and that your suggested ideas are not final. They are also subject to hardware limitations as well.
With that said, discuss the OTZ80 OS/software features here!

A couple of ideas moved from the hardware topic:
- Preloaded with Axe and math programs
- Calculus support (??) (Note: Derivatives, etc. maybe?)
- 3D graphing (??)

Feel free to elaborate on these or build on those ideas.

I think that if CAS is used, the calculator won't be allowed on SAT tests.

Maybe higher number accuracy would be good, like Cabamap except for non-integers as well (have the ability to view pi to 100 digits if you want).

Hmm I think 3D grpahing is quite intresting for say....derivatives. i think calculus support is quite a good idea. I think we should provide functions for users to solve the problems but no "solvers" that you just throw in a couple of variables and then..whoosh, there is your answer. We need them to program these for themselfs right?

No CAS?  Why not?  It's planned for KOS.

The only problem there is that the Z80 (and the eZ80 IIRC) has no "supervisor mode." This means any program can take full control of the calculator, pretending it's the official OS. The only solution I can see is to have a certain key combo or a special "push-to-test" button that would interrupt to read-only firmware that would put the calculator in PTT mode, preferably disabling ASM and possibly programs entirely (like PTT mode on the 84+(SE) OS, but with a simpler, foolproof invocation). Having hardware-based protection to try to protect certain things, like TI's protected ports on the 83+ Series, doesn't work very well since there are holes in the official OS (i.e. I could write a program for an 83+ Series calc that writes to flash)