I’m the developer of an android app, called App Greedy, that gives you the opportunity to gain money by completing some easy tasks like playing games, watching videos, etc. After completing some of the tasks you can redeem your points through a PayPal account or a gift card. It’s also great for you to invite your friends as you gain 50% points from them every time they complete tasks!
Fiverr is a popular platform for offering services. You can create your own Gigs to have available for sale. As the name suggests, Gigs are available to purchase starting at $5 though you can offer upsells to increase your earnings. You do need to wait 14 days between completing a Gig to being able to withdraw your earnings by PayPal. There are fees associated with these transactions.