The advent, evolution, and popularization of smartphones has transformed the nature of work and paved the way for completely digital employment. Many people now want to be able to work digitally in some capacity, whether for their primary source of income or to earn extra cash. Though independent contractors have been around for decades, there are now as many as 57 million freelancers working in the United States, helping to drive the development and spread of the gig economy.

Since Wi-Fi is almost universally accessible and 5G is becoming readily available, you can now make money wherever you are. From starting your own business to running a blog, there are now countless ways to make money using only your smartphone. You can even take advantage of money-making apps if you’re looking to start a side hustle or supplement your income. Between apps that help you invest or save your money and online surveys and games, here are a few of the best ways you can make money using your cell phone:

Investment apps.

There are myriad investment and savings apps that you can use to take control of your personal finances. Thanks to increased security measures for smartphones, you can safely and confidently take advantage of these investment apps to set yourself up for long-term financial success. Best of all, you don’t need a large amount of investment capital to get started.

Acorns: Acorns rounds up all of your purchases to the dollar and invests the difference automatically. It does cost $1 to $3 per month to use, but you can invest as much or as little as you choose.

Betterment: Betterment lets you calibrate the level of risk you're willing to take with your investments. That way, if you're willing to take a bigger risk, you might enjoy a bigger financial reward.

Invstr: Part investment app, part social network, and part fantasy game, Invstr is a solid choice to learn more about investing. You can play the fantasy stock to try different investing strategies, learn from other investors, and win real cash if you're a top performer.

Robinhood: Robinhood is a great option if you want to invest without worrying about paying commission fees, making it even easier to build your savings. They also offer other financial services, including stock trading and the option to invest in cryptocurrency.

TD Ameritrade: Created by a well-known brokerage firm, this app offers a full breakdown of your investments and portfolio, as well as information on different investment strategies.

Shopping apps.

Smartphones have also shifted modern shopping habits and made online transactions safer and more common than ever before. Now, with the help of the right app, you can make your usual purchases with greater savings and more deals available to you. In some cases, you may be able to make money or earn gift cards while you shop. 

Ibotta: The way Ibotta works is simple. Select the offers you’re interested in, complete one or more of their required tasks, buy the item, and provide proof of purchase to earn cash back. 

Paribus: Paribus helps you save money on purchases you’ve already made. If you buy something and the price drops afterward, Paribus will monitor the site for lower prices and request a refund for the value of the difference. 

Receipt Hog: This app lets you earn money on purchases you’re already planning on making. All you have to do is take a picture of your receipt. Then, on qualifying purchases, you’ll earn coins that can be redeemed for cash.

Swagbucks: Swagbucks also lets you earn rewards points in multiple ways, including online shopping, completing surveys, and watching videos. Once you earn a certain number of points, you can trade them in for gift cards or get cash back through PayPal.

Wikibuy: When you’re shopping online, Wikibuy will automatically look for better prices from other retailers, as well as coupons or other savings you’re eligible for. They also provide credit for loyal users that can be exchanged for gift cards.

Focus groups and surveys.

Filling out surveys, joining focus groups, and testing products are simple and straightforward ways to make some money online. Companies want to learn more about what you, as a consumer, think of their product or services - so much so that they're willing to pay you for your opinion. You may not be able to earn a substantial amount for these surveys, but they can still help you put a bit more cash in your pocket.

i-Say: On i-Say, you can earn points for completing surveys, participating in contests, or referring friends. Then, you can exchange your points for cash (via PayPal), popular gift cards, or Visa prepaid cards.

LifePoints: In addition to taking surveys, you can also submit diary entries and test products on LifePoints. You can then redeem the points you’ve earned for a PayPal payout or gift cards to major retailers, including Amazon and Starbucks.

MyPoints: MyPoints offers rewards for taking surveys, shopping, doing web searches, and even reading your emails. You can then redeem points for gift cards.

Survey Junkie: Survey Junkie is a well-known survey site that allows you to exchange the points you’ve earned for cash payments via PayPal or gift cards. You can also transfer your rewards directly into your bank account.

UserTesting: UserTesting allows you to provide your honest opinion on digital products through surveys and product testing. They claim you can earn $10 for every 20-minute test you take. All rewards are put directly into your PayPal account.

Play games, watch videos, or surf the web.

Nowadays, you can even make money by having fun online (or, at the very least, by going about your typical online activities). Some companies will pay you for streaming shows or movies, playing games, or doing web searches. Like taking surveys, you likely won’t be able to create a complete side hustle from these apps, but they do present an opportunity to earn cash while exploring a variety of entertainment options. While these apps will all run on a smartphone, it may be worth getting the larger screen size of a tablet to make full use of some of these interactive and game-based apps.

InboxDollars: InboxDollars lets you earn money for watching and interacting with the videos they select for you. You can also complete surveys, play games, and scan receipts.

Nielsen Digital Voice: After downloading the app, Nielsen will make note of your typical online activities and behaviors. The more you use their program, the more chances you have to win their monthly sweepstakes.

Slicethepie: Slicethepie will pay you for listening to new music. After listening to 90 seconds of a song, all you have to do is rate it on a scale from one to 10 and write a review. If you write more detailed reviews, you can earn more money.

Slidejoy: Slidejoy pays you for watching and interacting with ads. You can still earn points even if you reject or are uninterested in an ad. Points can be cashed out through PayPal or SquareCash.

Viggle: Viggle lets you earn rewards just for watching TV on streaming platforms like Netflix and Hulu. Your rewards can then be exchanged for merchandise offered by Viggle or for gift cards.

Sales.

You can also use apps to sell your gently used items, clothes, books, or electronics. Some apps will even pay you for pictures you've taken with your smartphone. As long as you can take good pictures with your phone, you can easily get rid of unwanted items and supplement your income.

Agora Images: With this app, you can sell pictures taken with your smartphone so they can be used as stock images. Unlike many other image-selling apps, Agora Images doesn’t have any commission or membership fees. You will also retain the rights to your images and can re-sell them to other businesses.

Decluttr: Decluttr helps you sell unwanted CDs, DVDs, games, books, and tech devices. They will instantly evaluate and price your items. You have 28 days to either accept their offer or find a better price elsewhere.

eBay: eBay has long been known as a website where you can sell your unwanted items, but their mobile app is just as useful for doing so. Your listings will even sync across your various devices so you can always keep an eye on your sales.

Letgo: Letgo lets you sell virtually anything you can to local buyers. Because you handle all payments yourself, you can haggle and try to make the most of your sale — and don’t have to worry about paying any commissions or fees to the app.

Poshmark: Poshmark is a great app if you’re looking to sell your unwanted clothing, shoes, and accessories. All transactions are protected by the company, so you will have to pay a small service fee on your sales.

Gigs and services.

Finally, there is no shortage of gig or service apps that you can use to build a side hustle or on an as-needed basis for additional income. No matter what your skills are, you're sure to find a gig job that works for you.

Fiverr: Fiverr is a marketplace for freelance workers looking for work in a wide variety of niches, ranging from digital marketing to computer programming. Depending on the services you offer, you could earn a decent amount of money selling your knowledge and expertise. 

Gigwalk: Gigwalk helps connect you with quick jobs in your area. Simply apply to a gig that interests you, complete the work, and then wait for approval from your customer. Payment will be directly deposited in your PayPal account.

Handy: Handy is similar to Fiverr and Gigwalk, but it focuses exclusively on jobs related to handiwork, such as small fixes and home cleaning. As you do more jobs, you could start to increase your rates and earn even more from Handy.

JustAnswer: JustAnswer allows users to pay experts in a variety of fields (ranging from engineering to tech support to law) for their opinions and advice. If you are knowledgeable in a certain area, this can be a great way to leverage your expertise for some extra cash.

Upwork: Upwork helps individuals with creative and computer-related skills find freelance work. If you’re great with graphic design or a master of marketing, it’s a reliable way to earn money quickly.

Both smartphones and the gig economy have taken enormous strides in the last few years alone. As a greater number of people look for digital work, there will likely be an even greater number of ways to make money using only your phone.