This is "referral coin" and team is basically asking people to find as much referrals as they can (they have 4 million users as far as I know) and I suspect this is some kind of attempt to collect as much private information they can.
There is some "phone-mining" going on, but tricky part is that if you want to receive Pi coins you will have to provide them your KYC otherwise your "mined" coins will be removed (note: it is not known what happens to removed coins). Nothing really explains how they can remove coins which someone mined, but if they can do that I wouldn't go near this. Imagine, you mine bitcoin and satoshi remove them because you didn't provide them your private info
Ask promoters "what is purpose of this coin, where will I use it?", I am pretty sure not single one of them know answer
There is some "phone-mining" going on, but tricky part is that if you want to receive Pi coins you will have to provide them your KYC otherwise your "mined" coins will be removed (note: it is not known what happens to removed coins). Nothing really explains how they can remove coins which someone mined, but if they can do that I wouldn't go near this. Imagine, you mine bitcoin and satoshi remove them because you didn't provide them your private info
Ask promoters "what is purpose of this coin, where will I use it?", I am pretty sure not single one of them know answer