If you're single and browsing the dating app world, you're probably in the market for other single ladies and fellas out there to chat with online. You're most likely not interested in meeting people who are in committed relationships or are married when browsing nonaffair sites like Tinder or Bumble. Unfortunately, you never know who is really behind that profile. Earlier this year, Tinder crashed nationwide, and there was a surge in Ashley Madison by 20 percent with new member sign-ups in both the US and the UK. Why? Well, according to a 2015 survey of around 1,282 active Tinder users (at the time there were around 50 million people on Tinder), nearly 30 percent of Tinder users are married, while another 12 percent are in a relationship. Yikes. While this was a small sampling, and who really knows if people tell the truth in those kinds of surveys, it is a good reminder to keep your guard up when you're dating online. Don't fall for liars on Tinder and other dating apps - prepare yourself with these tips. Here are the red flags to look out for that someone you meet on a dating site is either married or taken.