I originally found the ti89.com website by surfing the web trying to find ways to help with my physics class.
After downloading my first app I loved it!
Helped in so many ways especially when they do step by step.
I downloaded my second app a year later taking my differential equation class. It easily helped me understand the class and the equations being used.
What is even more outstanding is the customer service.
Quick response and help whenever needed.
Highly recommend these apps at ti89.com to anyone needing a little help with classes and a efficient tool to succeed!