Download:
http://www.ticalc.org/archives/files/fileinfo/429/42961.html

Some quick info:

Recently on TI-Bank came out v3.0 of AutoCalc, a CAS program for z80 made by Xavier Andréani. Even though it is quite awesome, the large amount of programs that it uses and the not-so-friendly GUI have made it quite difficult to use. Therefore, I made an app version of this program (using BasicBuilder), with a cleaner GUI and with Symbolic and PrettyPrint (the app, not TI's MP OS) support.

Instructions:

The app uses a command line style interface, similar to the one used by TI on the homecreen.
For calculations, just type them in and wait.
To exit the app, type QUIT.
If you forgot the syntax for the Symbolic and PrettyPrint functions, type HELP.
If it is taking forever to calculate the result and you want to abandon, press the On button. You'll have to relaunch the app after this, though.

Other functions, requiring Symbolic and/or PrettyPrint, have a slightly different syntax (the ":" character that appears in some of the functions HAS to be used for the functions to be recognized):


derivates the expression with respect to X
PD: same as above but also outputs the result using PrettPrint
SIMP: simplifies the expression
PNUM: the standard CAS calculation, but with PrettyPrint output
PEXP: simplifies an expression and then outputs the result using PrettyPrint
PRON enables AutoPrettyPrint, so that all functions and calculations automatically output their results in PrettyPrint
PROFF disables AutoPrettyPrint

The app automatically saves your AutoPrettyPrint settings, so that you don't have to modify them each time you run it.
Also, the app saves the last result into the Ans var and Str0, so that it can be used after quitting the app.
The app has been made so that Symbolic and PrettyPrint are optional, meaning that it will work without them, though with less functions available. The main CAS calculator engine doesn't require Symbolic to work properly.
I also recommend using Omnicalc to install Symbolic, since this allows faster loading times and other nifty functions.

I would be very grateful if you tested all of its functions and reported any bugs in this thread. Thanks.

*bump*
Here you go, you can now have all the details in my 1st post!

It says in the readme that as long as I give credit to him, I can use his programs as I want.

*bump*

And voilà, I've finally finished! Check out the app and instructions in my 1st post!

When I meant calculations, I meant things like "(e^3/2)*Pi". If you want to make calculations with X, use the SIMP: function instead.

This sounds pretty neat.   What math class is this most useful for? 
Nice job.

*bump* (excuse me for the double post)
File submitted to queue on ticalc.org and already available on TI-Bank.

NB: I also submitted some older programs on ticalc.org, such as "Link's Puzzle Challenge" and "xDCS GUI Editor".

Important update!!!

Fixed major bug which makes the app crash if you quit it without making any calculations! New file attached to 1st post.

@ztrumpet: No idea. But I hope it'll be today or tomorrow.