Enlarge / Apple Watch Series 3, with eSIM technology for connecting to cellular networks. (credit: Apple) AT&T and Verizon are being investigated by the Department of Justice (DOJ) over whether they colluded in order to prevent customers from easily switching carriers. The antitrust investigation, reported by The New York Times yesterday, relates to the eSIM (embedded SIM) technology that is used instead of regular SIM cards in cellular-capable Apple Watches and other devices such as the Google Pixel 2.