T-Mobile Starlink is obviously available to T-Mobile customers, but the carrier said that Verizon and AT&T customers can also use it on their existing phones without switching entirely to T-Mobile. Verizon and AT&T customers will need an unlocked phone with eSIM technology, which lets users activate a cellular plan without a physical SIM card.

T-Mobile’s Starlink-powered direct-to-cell satellite messaging service is now open for anyone in the US to try for free — including people who aren’t T-Mobile customers. The service will be limited to text messaging at first but the company hopes to have some apps and even limited multimedia support ready by the time it goes live this summer.