An anonymous reader cites an article on The Guardian: Tinder isn't as private as many of its users think, and a new website which aims to exploit that is causing concern among users of the dating app Swipebuster promises to let Tinder users find out whether people they know have an account on the dating app, and even stalk them down to their last known location. The website charges $4.99 to let someone see whether the target is using Tinder, and can narrow down results by first name, age, gender and location. But it doesn't do so by hacking into Tinder, or even by "scraping" the app manually. Instead, it searches the database using Tinder's official API, which is intended for use by third-party developers who want to write software that plugs in with the site. All the information that it can reveal is considered public by the company, and revealed through the API with few safeguards.