This app saved me $120 in Las Vegas - and can save you even more

Earlier this week, my girlfriend and I took a trip to Las Vegas.

In an effort to make every dime count, we downloaded an app called MyVegas.

MyVegas is a pair of apps for Facebook, iPhone, and Android where you play blackjack or the slot machines with virtual cash - and earn real rewards, like meals and show tickets, at some of Las Vegas' biggest hotels and resorts.

With less than a month of playing MyVegas, and some smart strategizing, we earned enough of the game's "loyalty points" to save around $120 on our Vegas vacation. If you're forewarned, you can save even more.

Here's how it works.