5 apps that can earn you cold, hard cash (and other rewards) If you want to make a little cash on the side, thes

That expensive smartphone in your pocket could pay for itself -- you just have to download the right apps. Both the Apple App Store and Google Play Store are littered with titles to help you rack up money, gift cards, and other perks, and all you have to do is give up a few minutes of your time to earn your share. I've rounded up five apps here that are easy to use, and don't require too much hassle to get your money.

First, heed my warning: If an app that promises you money sounds to good to be true, it probably is. While the App Store has stringent requirements that must be met before Apple will publish an app, thus keeping most scams at bay, the Google Play Store has a fair number of "get rich quick" apps that are flat-out hoaxes. That said, the apps I included in this list are safe to use and do what they promise.

Screenshot by Sarah Mitroff/CNET
Rewardable (Free, iOS and Android)
One of the newest apps in this category, Rewardable gives you specific tasks to complete and pays you cash for your efforts. There are two kinds of tasks: ones you can complete online from your smartphone, and ones which require you to walk into a store, answer a few questions and maybe take a couple of pictures.

Companies use the app for secret shopper tasks, such as checking out a display, and for testing the functionality of an app or Web site. Jobs change over time, and when I was playing around with Rewardable for this post, the top job was to go into west coast supermarket chain Safeway, check out a drink mixer display, take a photo, and answer a few questions to earn $4. Most jobs pay out around $5, with the higher paying ones topping out around $20, and you get paid via PayPal.

Unlike other apps, Rewardable also gives you digital jobs to complete, so if there are no available jobs at brick-and-mortar stores in your area, you can still earn money. With all assignments, once they are completed, the Rewardable team reviews your answers and then sends your payment to the app.

Good: The app has virtual tasks anyone can complete, whether you live close to a physical task or not.
Bad: Payouts are on the smaller side, typically $5.

Screenshot by Sarah Mitroff/CNET
Gigwalk (Free, iOS and Android)
Gigwalk has been around for several years, and like Rewardable, it pays you for completing tasks in your area. Gigwalk has higher payouts than I've seen in other apps, but the jobs are often more labor-intensive, and you must apply and be approved before you can complete them.

For example, one job I found pays $19 to go to a specific Home Depot store location and check that Red Bull display fridges are set up in the store and properly stocked. You're supposed to take photos of the refrigerators and write notes about their location to complete the job.

Most gigs ask you to go to a store and check out a display to make sure everything looks right. You snap photos and record your notes, occasionally talk to a manager about what you saw, then submit your work for review. If you complete the job correctly, you get paid via PayPal. The typical payout is between $5 and $20.

As you complete more jobs and get positive ratings from clients, your reputation in the app improves and you can unlock higher-paying jobs.

Good: You can unlock better-paying jobs over time to earn more money.
Bad: You must apply and be approved to complete a job.

iPoll (Free, iOS and Android)
If you live to share your opinions, iPoll is the right app for you. The app collects market research by asking you to complete surveys, called missions, in exchange for cash. Some missions are location-based, meaning you're supposed to go to a physical business and answer multiple choice questions about your experience or any products you purchased. Other missions ask you to watch a video or fill out a general survey to earn money.

What I like about iPoll is that there seems to be more real-world location tasks than other apps I've tried, which means there's a good chance you'll be able to find several missions to complete in your area. For example, I completed a bank mission that let me choose from several different banks and ATMs in my area, including Chase, Bank of America, and Wells Fargo.

Most missions pay $1 and take around 3 minutes to complete, and there's also a $5 bonus just for signing up. Once you earn $10, you can cash out your earnings on iPoll.com.

Good: iPoll has a lot of missions to choose from, so chances are good you'll be able to find some in your area.
Bad: The app's design is hard to navigate at times.

Screenshot by Sarah Mitroff/CNET
Google Opinion Rewards (Free, Android only)
While this app doesn't give you cold, hard cash, it does reward you with Google Play credits, which you can redeem for Android apps, Google Music, Books, Magazines, or Movies in the Play Store. The catch here is that you have to give your personal opinions (either real or fake, you can decide how truthful you want to be) over to Google, which then gives them to marketers and companies looking to gather consumer views.

Once you sign up, you'll get a handful of surveys per week, depending on your demographic, that ask you a few short multiple choice questions. Rewards vary from 25 cents to a dollar or more, depending on how much information you can provide and the length of the survey. Because the app is owned by Google, it's really easy to connect the Play credits you earn to your Google account and redeem them for anything in the Play Store. It takes time to earn enough credit for books or movies, but you can earn enough for an app after just one or two surveys.

Good: The app is really easy to use and notifies you when there's a new survey available.
Bad: You can only earn Google Play credit, not cash.

Screenshot by Sarah Mitroff/CNET
Shopkick (Free, iOS and Android)
Shopkick requires a bit of patience, but if you're a frequent shopper, you can quickly rack up enough points to earn gift cards and other prizes. You can earn perks by just stepping into a store and scanning an item or making a purchase.

Shopkick works with retailers including Target, Old Navy, and Macy's to install beacons in their stores. When you walk into the store and open the app, your phone communicates with the beacon and gives you points. Some stores also have promotions that ask you to scan a particular item with the app's barcode scanner to get points.

The point of Shopkick is to get you into a store to check out specific promoted products so that you're more likely to make a purchase. However, you're rewarded for your shopping behavior whether you make a purchase or not.

Once you accumulate enough points, you can redeem them for gift cards to Target, Sephora, or Macy's (to name a few), or other prizes, such as a Dyson vacuum, magazine subscription, or a TV.

Good: You can earn rewards for just walking into a store and opening the app, which takes only a few seconds.
Bad: It can take a long time to gather enough points for a reward, depending how much you shop.