WhatsApp has been working on adding support for usernames for some time now, and while the feature hasn't been made public yet, the service has now added an interesting twist.
In the latest beta version of WhatsApp for Android (2.24.18.2), you can set a username PIN so that people you haven't interacted with before can't just message you if they know your username.
This seems like an incredibly useful feature that should cut down on spam (which is a common problem on WhatsApp these days). With the PIN, if someone you've never interacted with before on WhatsApp wants to message you, they'll not only need to know your username, but also your PIN (which will need to be at least four digits).
Conversations with people you're already in contact with, however, will continue as if nothing had changed, even after usernames are implemented for everyone.
Unfortunately, there's no word on when the username feature or PIN support will be coming out of beta, but judging by WhatsApp's usual development time, we'd be surprised to see them go live before the end of the year.
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