Have an Android phone? -- Here's how to legally get 10-20 free apps and in-app purchases of your choice every year.

I came across this when I was trying to figure out how to score some free Lures for Pokémon Go. (Lame, I know.) Check out Google Opinion Rewards, it's only available for Google Play on Android Phones:

You can average between $10-$20 per year from what other people have said and from what I've personally seen so far. I usually get a 3-question survey a couple times a week and it pays $0.20-$0.30 each. It's quick and easy and it adds up. 

Caveat - Don't bother using this if you don't travel outside the house at all because you probably won't receive any surveys. Also don't use this if you're paranoid about government tracking of any sort, because you definitely are being tracked when you use it. 

(But let's be real, we're all being tracked anyway, and if you're in this boat you would already know to avoid all Google services.)