An email address consists of a local-part (part to left of @) and a list of domains following the @. This app only allows simple email addresses of the form
[email protected]. Not everyone has email addresses of that form. I don’t. Mine happens to look like
[email protected]. Bottom line, I CAN’T REGISTER! Such email addresses result in an error message from the app (“Something went wrong”) when I attempt to use my desired address to sign up. If you are going to accept email addresses then you should accept the full syntax. For starters I suggest you look at Wiki for “email address syntax”.