Imagine how different your life would be if you didn't have your phone and favorite smartphone apps. We download and use apps all the time to make our lives easier, gain knowledge, or just for fun and entertainment.

The smartphone you're holding in your hand is basically like a mini-computer. Since most of us know how easy it can be to make money online, it can be just as easy to make money with smartphone apps.

Here are 10 of the best smartphone apps you can use to make extra money in a flexible way.

RELATED: How to Earn Easy Extra Money From Your Smartphone

1. S'more

S'more is an app that lets users earn rewards via their lock screens by displaying targeted ads. Users receive points daily for having the ads on their lock screens, and these points can be redeemed for gift cards from popular retailers, providing a simple way to earn passive income. A recent review suggest users can earn $50 or more annually in addition to other rewards.

2. Inbox Dollars

Inbox Dollars is a free app that allows you to make money by completing short tasks like surveys, surfing the web, reading email, etc. You can redeem your earnings once you have a balance of at least $30. The app has paid users $30 million in cash rewards since 2006. You can get a $5 bonus when you first sign up.

3. Ibotta

Ibotta is a rebates app that pays you cash back for purchases you make in stores and online. Just unlock offers on the app and then scan your receipts to earn cash back.

Ibotta is a great app to use when you're grocery shopping or buying regular household items. Since you have to spend the money anyway, you might as well earn some cash back.

4. Swagbucks

Swagbucks is one of my favorite apps to use to make extra money. Like Inbox Dollars, you can earn points by taking surveys, trying out offers, and searching online. But you can also earn points by playing games and watching videos.

Since I work from home, I use the Swagbucks search engine instead of Google so I can effortlessly rack up points during the day. You can redeem your Swagbucks for gift cards or cash via PayPal.

I'm currently using Swagbucks to earn $50 in gift cards that I can use for holiday shopping.

5. Earny

The Earny app is a platform that helps users save money on their online purchases. It monitors price drops on items users have bought and automatically files claims for refunds on their behalf if the price goes down. Users earn money by receiving refunds for the price differences on their past purchases, effectively helping them get the best deal even after their initial purchase.

6. Money Lion

Maybe you got rewards when you were younger for doing chores and staying organized. As an adult, you're just expected to take care of your responsibilities like paying your bills.

Money Lion is an app that actually rewards you for paying your bills on time. The app helps you develop financially healthy habits and earn rewards that you can redeem for gift cards to retailers like Amazon, Apple, and Walmart. The app also connects to your credit card, bank, and student loan accounts.

7. Decluttr

Decluttr allows you to sell your old books, movies, cell phones, and electronics for cash. Once you provide information about the items you want to sell, Decluttr will offer you a quote and send you materials to ship the item to them.

Once the items are received, you get paid. You can also make money by referring other people to Decluttr.

8. iPoll

iPoll is a smartphone app that users can use to take 15 – 20-minute surveys to earn gift cards, airline miles, etc. You can use the app with your Android or iPhone and earn gift cards to popular retailers as you rack up points.

9. Gigwalk

Gigwalk is a workforce management platform where you can connect with local businesses who need contract work done. Just download the app and register so you can start applying for gigs. Gigs pay anywhere from $3 to $100 via PayPal depending on the nature of the task.

10. DietBet

Thinking about losing weight or getting back in shape? There are apps that will pay you to do that. One of the most popular options is DietBet. With DietBet, you create or join a group and everyone puts money in as they bet to lose a certain number of points within a specific time frame. You usually put $25 in the pot to join but if you win your bet, you get to keep the whole pot minus DietBet's fees.

Have you ever thought about making money with smartphone apps? Which one of these would you consider using?