UPDATE: As of around 1:00, Gchat appears to be returning sporadically for some. The company’s G Suite Dashboard is also showing no disruptions in Google Hangout service. [More]
google hangouts

AT&T Customers Will Probably Have To Wait Before Using Google Hangouts Over Cellular
If you’ve got an Android phone, you might have noticed that your pre-loaded Google Talk app has recently been updated and is now “Hangouts,” the name of Google’s video chat service. But if you’re an AT&T customer, you might have to wait a while before you’re allowed to use that app over the carrier’s wireless network. [More]