Google Rewards! It asks you simple questions randomly and gives you a little bit of actual money. It really helps out when I don't want to pay for a micro transaction I actually do want! Usually it's dumb pay only power ups when I'm in a tight spot or stickers for photos but it has vastly improved my experience on all apps that require money sometimes. I started in 2017 and have earned $78 so far. All of it has been spent on microtransactions, but I believe there is the option to transfer somewhere.