U.S. coffee chain Dunkin' Donuts today launched free mobile-payment apps for Apple iOS and Google Android devices, in an effort to capitalize on the popularity of mobile payments apps from its rival, Starbucks.

I drink my fair share of coffee, most of it from two specific coffee chains: Starbucks and Dunkin' Donuts. In fact, I have a big ol' cup of Dunkin' java next to my keyboard as I write this.

One of the few mobile-payments apps I actually use is Starbucks' mobile coffee card app, which has been available for years. The app is simple to use, and it lets you not only pay for your coffee with your smartphone, but also reload your Starbucks loyalty card and earn rewards, as well as find Starbucks locations near you.

Starting today, you can also pay for your Dunkin' Donuts coffee with a smartphone, thanks to the brand new Dunkin' Donuts apps for iOS and Android devices. (The app is not compatible with Android tablets, but it should work on the iPad.)

The Dunkin' apps are very similar to the Starbucks apps; you just connect your coffee-cards to your online account and then bring up a barcode that a Dunkin' cashier then scans for payment.