Generally a lot of peoples use apps like 4fun to earn money. But sometimes using these apps can be boring and also time wasting.
Apps like 4fun get a lot of rating at play store because they give their users little coins for rating.
Another problem is that they bombard you with the ads to get money from Google adsense.
So, if you guys don’t want to waste your time. I advice you not to use 4fun app.