YAHOO LIFESTYLE - July 12 - On Lumen, only those who are 50 or older are allowed to join. It also requires users to upload a selfie in order to verify their identity - a unique feature that reduces the risk of catfishing. Users have to upload at least three photos. There's also a minimum character length for the messages and a limit to how many matches users can contact, so people can't just spam hundreds of users without reading their profiles. They only have 72 hours to respond to someone's message.