Most of you must have heard of the Pi network. It has been around for a while without giving any kind of reward to its users. I never joined it and i am glad i didn't fall for it. A few of my relatives though are still mining Pi on their mobiles. But here is an article of why it might not worth the time
https://coinmarketcap.com/alexandria/article/pi-network-where-the-mining-never-stops-and-looks-like-it-never-willI still believe that the number of users this network has, it can do wonders by doing some ventures with some companies even just by marketing. But it seems its not just interested in any reward and just want to eat the time of the people who trusted in this pathetic application.