[bikamonki]

Why require the number? So you can send an activation/recovery code over SMS? Virtual numbers and pre-activated SIMs are easily accessible nowadays. You'd mitigate but not prevent abuse nor spam. In terms of security, SMS is NOT recommended to communicate sensitive data.

That being said, only a tiny few of us are concerned about privacy, most app users aren't, otherwise FB wouldn't have a billion users.

[warewolf]

These are really great points. The thought process is that it will be used for authentication and recovery. I would say Virtual Numbers are a concern but most cost money and an email is free to create. Which was why I said better control spam. If they want to pay money to be a clown and troll I've already won anyway.

I think you are right about the concern of privacy. The scary part is most don't even read the Terms and Policy Agreement.