I'm going to hopefully avoid netiquette breach with my +1 for Signal by adding details.
First time trying last week. I dont use anything other than Signal (and I guess google chat by default with email).
Signal was fine on some (IAD-DEN/B738, IAH-IAD/A320) but I had very spotty results over the Rockes (DEN-RNO/B738, RNO-IAH/E75L)
Dont really know whether to attribute the problems to geography or equipment. It never really got better on the RNO-IAH leg, so I just figure the rollout continues.