There are a lot of things you need to be aware of. I used to get scammed quite a lot. Some apps do look legit, but they are still scams. However, most applications do have huge red flags. One of the biggest ones is a huge claim for money. Any app that claims to earn $100 won't pay you. Another thing is reviews. If the reviews are 5 stars, then that might be another red flag. Most of the time, developers use fake reviews to boost their apps. If you have Goofle Play and the app is in early access, there is a high chance that it is also a scam.