Social media texts? That’s so 2020. When you are involved in a big-time insurrection, you need a quicker form of communication, like a “push-to- talk” mobile app. But authorities might be on to you. Is there other technology? Always, it seems. Heightened activity around Zello, a mobile walkie-talkie app, occurred when it found itself being used by right-wing militia members who participated in the insurrection on Jan.