PocketCAS, the free Computer Algebra System (CAS) offers you quick access to solutions of mathematical problems on your PDA.

Solving advanced mathematical problems made easy
PocketCAS is a free interface to the open-source Computer Algebra System giac/xcas. xcas enables you to quickly solve complex algebraic problems, e.g. symbolic and numeric integration and derivation of non-trivial functions, solving differential equations etc.

It has also a huge support for problems of linear algebra, like solving linear equation systems, multiplying and inverting matrices, finding eigenvalues (and eigenvectors, of course) and much more.

If you do statistics or number theory, you will like xcas' great functionality in those areas, too!

Built-in TeX output
PocketCAS has the option to automatically use the output of xcas to generate beautiful formula images using mimeTeX. Just enter an expression and you will get the result in the same formatting you would find in a mathematical textbook!

For example, other Computer Algebra Systems would output the following result to the command integrate(sin(x)*cos(x)):(sin(x))^2/2

With PocketCAS, you will see:

(this is VGA output, on your PDA it will look smaller and even smoother!)

More screenshots here. Get more information on the author's website.

Simple input method for faster solutions
PocketCAS contains a fully-customizable, easy to use mathematical keyboard for quick input of most mathematical functions. You can even assign images to displayed on a button rather than mere text!

Therefore, PocketCAS is as simple to use as a pocket calculator, but provides you with the functionality of a full-blown CAS - in your pocket, wherever you take your PDA with you!

Missing a function or a macro? Simply add it to the keyboard which is stored in a human-editable XML-file!

System Requirements
PocketCAS needs the following:
- About 3 Megabytes of free internal storage (installation on a storage card might be possible).
    o Maybe I will provide a version with non-UPXed xcas later, which will need about 7 MB of storage but less RAM.
- At least 64 MB of RAM in total installed in your device (96 MB for Windows Mobile 2003 devices).
    o The PocketCAS executable needs less than 1 MB RAM, but during calculations, xcas needs 6 - 7 MB RAM.
- .NET Compact Framework 2.0 or newer installed on your device.
- At least Windows Mobile 5.0 to display images rather than text on the mathematical keyboard, Windows Mobile 2003 or later will work but won't display images.

Update Description:
v1.1.0 Performace Edition (11-09-2008):
- PocketCAS now is distributed via four different CAB files, depending on your device, see Download page for more details.
- Lines prefixed with an @ letter will be hidden in TeX output mode. This prefix has no effect in non-TeX mode.
- Lines prefixed with a // will not be processed by xcas at all. This way you can easily add comments to your scripts.
- Bug fixed: 3*4 will now be shown as 3*4 rather than 34 if using TeX mode.
- Bug fixed: ifactor(15) will return 15 rather than 3*5 if not using TeX mode.
- Menu redesign (more sub-menus to increase clarity).
- Added a feature to save an image of the last result (File->Save as image).
- Links on the about page are working now.
- Replaced the UPX'ed MimeTeX executables by non-UPX'ed ones for an additional performance boost.
- Several other performance improvements.
- History function (you get a list of the last commands you entered and you can select which one to execute and edit).
- A server executable which will be started upon loading PocketCAS and will stay loaded so that single calculations can be performed much faster.
    o Some results are generated (and TeXed!) in less than a second!
    o The effect of commands entered before will not be discarded. Therefore previous declarations of variables will work in commands entered later, too.

v1.0.2 Greek Edition (29-08-2008):
- Added images for the following functions: x^(-1), x^y, e^x, sum, product.
- Improved images for the following functions: sqrt, integral, pi.
- Some internal optimizations regarding the XML keyboard. Please tell me whether you notice changes in performance and memory consumption (good or bad).
- Greek keys and keys for single-letter variables for easier variable input (located in the "helper" section).
- Added more mathematical symbols to the keyboard rather than mere text. This benefits WM 2003 users especially, as they now get some icons rather than mere text buttons.
- Improved options for keyboard font sizes (different font sizes for individual sections and buttons).
    o Text size of many keyboard buttons has been improved for even better usability.

v1.0.1 (12-08-2008):
- Changed integration function from int(...) to integrate(...) in keyboard.xml. This shows an integration symbol in TeX output.
- Added images for the following functions: sqrt, approx, backspace, newline.

v1.0.0 (06-08-2008):
- First public release.