L.A.-based software engineers Devin Calloway and Julian Cain are also medical cannabis patients. And they're looking to "harvest change."

Over the last several months, Calloway, 24, and Cain, 32, matched their programming talents to their political passions to put Cannabis up for sale on iTunes. The price? $2.99.

Cannabis is a geolocation-based iPhone app that allows users to quickly find the nearest medical marijuana dispensary as well as weed-friendly doctors and lawyers, all with a few quick touches.

The app has sold more than 1,000 units, and its founders said they planned to put 50 cents of every purchase -- or 17% of the proceeds -- toward establishing a nonprofit organization dedicated to media outreach for the pro-pot cause.

The idea behind the app is to "use technology to empower the medical cannabis industry and the global hemp movement," Calloway said.

In California and other states, the substance is legal with a doctor’s prescription but remains illegal under federal law.

Calloway is a founding member of ajnag.com -- that's ganja backwards -- which stands for Activists Justifying the Natural Agriculture of Ganja. According to Calloway, the website was the first comprehensive online map of...