The Un-carrier today launched the T-Mobile eSIM app. Now, travelers to the U.S. and others can use the eSIM on the latest iPhones to add a secondary prepaid line to any unlocked iPhone XS, iPhone XS Max, and iPhone XR. By launching an iOS app, T-Mobile is making it simple to light up eSIM. Just download the app and select a prepaid plan that works for you. No trekking to a store or juggling two different physical SIM cards – adding a line is done from the convenience of the app, wherever you are.