MATLAB to web app
A cheap and somewhat easy way (with limited functionality) would be:
Install MATLAB on your server, or use the MATLAB Compiler to create a stand alone executable (not sure if that comes with your version of MATLAB or not). If you don't have the compiler and can't install MATLAB on your server, you could always go to a freelancing site such as elance.com, and pay someone $20 to compile your code for you into a windows exe file. 
Either way, the end goal is to make your MATLAB function callable from the command line (the server will be doing the calling) You could make your input arguments into the slider value, and the .mat files you want to open, and the compiled version of MATLAB will know how to handle this. Once you do that, have the code create a plot and save an image of it. (using getframe or other figure export tools, check out FEX). Have your server output this image to the client.
Tah-dah, you have a crappy low cost work around! 
I hope this helps , if not, I apologize!
Hi I have a MATLAB function that graphs the trajectory of different divers (the Olympic sport diving) depending on the position of a slider at the bottom of the window. The file takes multiple .mat files (with trajectory information in 3 dimensions) as input. I am trying to put this MATLAB app on to the internet. What would be the easiest/most efficient way of doing this? I have experience programming in Python and little experience programming in Java.
Here are the options that I have considered:
1. MATLAB Builder JA (too expensive)
2. Rewrite entire MATLAB function into Java (not experienced enough in Java)
3. Implement MATLAB file using mlabwrapper and using Django to deploy into web app. (having a lot of trouble installing mlabwrapper onto OSX)
4. Rewrite MATLAB function into Python using SciPy, NumPy, and matlibplot and then using Django.
I do not have any experience with Django but I am willing to learn it. Can someone point me in the right direction?