THE NEW YORKER - Feeld describes itself as a technology for "open-minded singles and couples who want to explore their sexuality." It is free to sign up, although a paid membership, priced at $12/month, offers perks such as filters and let someone know that they like them. The app started in London. The app is popular with nonbinary and trans people, married couples trying to spice up their sex lives, hard-core B.D.S.M. enthusiasts, and "digisexuals," who prefer their erotic contact with others mediated by a screen. According to the company's data, the typical Feeld user is between twenty-five and thirty years old and lives in a big city. Feeld began, in 2014, with the story of Dimo Trifonov and Ana Kirova, two Bulgarian graphic designers in their early twenties who were living in London. Early in their relationship, Ana started having unexpected feelings for a French woman she'd met. They agreed to open their relationship. Trifonov decided to create his own app to facilitate threesomes. He called the project 3nder. After Tinder a cease-and-desist letter, which was followed by a trademark-infringement lawsuit, Trifonov rebranded the company as Feeld.