Most iPhone games are good for little more than mindlessly killing time. Yes Candy Crush, I'm looking at you. But every now and then, an app comes along that provides the opportunity to have fun and contribute to a good cause.

And that's exactly what Pocket Rice [No Longer Available] is.

With Pocket Rice, you can answer general trivia questions or go for one of ten specific categories: Arts and Letters, Film, Geography, History, Miscellaneous, Music, Science, Society, Sports, or Technology. You can scroll through the categories by tapping the arrow button in the orange bar.

Unlike other iOS trivia apps, however, for every question you get right, it will result in 10 grains of rice donated. As you answer questions correctly and accumulate the rice grains, you can then donate those grains to their current program.

The current donations are going to a nutrition program in Sri Lanka aiming to reduce child mortality in cooperation with Lasallian Foundation.

According to the app, over 10,000 people have been fed and over 200 million grains of rice earned. And you can keep track of how much you've donated in total as well.

If you don't have an iPhone app and would like to contribute through a similar game check out Free Rice. The trivia website also donates 10 grains of rice for every question answered correctly, having teamed up with the UN's World Food Program. To play, you will have to sign up for a free account.

What do you think of games like Pocket Rice and Free Rice? Let us know in the comments.