I was wondering what people might think is the best way to stop a single person from creating multiple accounts on an app. Going in, I know that no solution will be perfect, but some of the ideas I have thought of around using IP addresses might not be all that great since it might create a lot of unwanted false positives.
Thanks in advance for any ideas or strategies!
I think the IP address is probably the best way to go on sign up. Save the user’s IP address in the user data type. Then when signing a new user up you can check the current user’s IP address against the database before signing them up. If they are already in the database then send a error saying you already signed up with a different email address.
Why do you think there will be false positives?
Of course, they will be able to sign up on different devices. Not sure how to stop that.
Hope that helps! 
Maybe phone verification could do it ?
Thanks @J805, that is a simple enough solution. I guess I am only somewhat familiar with IP addresses after doing my research. My understanding is devices on the same network can share the same exact IP address - which would potentially be a source of false positives. Correct me if I am wrong of course! I could implement this immediately if you think I am being too cautious.
@vnihoul77 I really like that idea as maybe a more long term solution since it is much harder to create multiple phone numbers compared to multiple email addresses. Any plugins/APIs you might recommend?
According to https://www.lexico.com/definition/ip_address each computer has it’s own IP address.
Hope that helps!
@lortie.jason I was using Clicksend SMS (there is a plugin available very easy to use, and pretty cheap) combined with a random number generator plugin to send verification code.
