Contents

Envelope Credits

Benjamin B. Spratling IV

Dr. Graham B. Booker



www.MathTouchApp.com
www.benspratling.com
www.biblexpress.com
www.pocketfishing.com



Astronomical observations and images copyright Jet Propulsion Lab, NASA.

Unit values: NIST, www.nist.gov

The Story of Math Touch

Although he studied physical science in college, Ben Spratling was bitten by the software bug: the desire to solve a problem only once, and have a computer do it thereafter. While the available tools and software could compute the numerical solutions to problems, they lacked a fundamental need: representing the physical quantities instead of representing only numbers. Without the physical significance represented directly in the software, engineers and scienctists have been using computers as nothing more than fast slide rules, doing the dimensional analysis, unit conversion, coordinate system by hand separately (as if that was the best way!). He began developing software for his own use that represented the physical significance of values, making unit conversion essentially automatic. With this system, physical values have a real meaning, and the relationship between dimensions is automatic.

Then in 2007 Steve Jobs announced that the iPhone app store, which would make an easy way for a small app like a dimensional analyzing unit converter to be distributed. When the App Store opened in 2008, Ben had a unit converter on the store, called "Units" which performed dimensional analysis. Now, scientists and engineers could convert units and get a notice that they've made a mistake with the dimensional analysis and add their own field's conventions into the unit database.

As an aerospace engineering graduate student at Texas A&M University, Ben would frequently get "what if" questions from his friends about engineering. One day at lunch, his friends asked how large solar cells would need to be to provide enoug energy for a regular-sized car to travel on the road at 70 mph. Ben remembered all the appropriate formulas and constants, and was able to use his iPhone app to do the conversions, but solving each equation was done painstakingly on the back of a napkin!

Later that week, Ben's friend Graham visited Ben and proposed they work together on a new app to eliminate the tedious work of those calculations that would combine Ben's unit conversion and dimensional analysis with a visual equation linking system. Ben and Graham, who was a graduate student in computer engineering at A&M, went to work designing the application from the ground up. The new app would have no traditional command line, variables in equations would be more than just letters, but the letters would remain to maintain a sense of physical significance. The variables would be linked visually instead of by just the name alone. Numbers would always keep track of their precision, and vectors operations would work correctly no matter the coordinate system. Plotting would gain all the benefits of a multi-touch device. Ben and Graham had no investment capital, no employees, and no office for their collaboration.

They worked at all hours of the night, weekends, and during vacation in their apartments' living rooms and kitchen tables using their notebook computers and two or three textbooks. Though they searched for a computer algebra package to use inside, no available package met their requirements. Math Touch was to have a completely new system from the ground up, designed for handling exactly the kinds of problems back-of-the-napkin solutions presented.

The iPhone OS was updated twice before this app was ready. Two years of hard work every time they had a chance, and what you see before you is the result. It's by no means to extent of their vision, but it's a self-consistent set of functionality for solving back-of-the-napkin calculations that forms the beginning for a new kind of scientific and engineering computation: one in which the scientists and engineers win because the computer now understands physical quantities. The user now interacts directly as they think instead of in the way a computer programmer thinks. It's time to throw away your scientific calculator and use Math Touch.

I've worked hard to bring this app to you, giving up sleep many nights over the past two years. It's not everything I want it to be yet, but I look forward to adding new features as you buy and reccommend the app.

-Ben Spratling