Absolutely fantastic. Could not recommend this app enough.
This is probably the single most convenient app you could have on your phone when flying into the US. Fill in your passport details, answer a few questions, take a selfie (all of this can be done in 5 minutes on the plane while taxiing to the terminal after landing) - and through you go with no queue whatsoever when you get to passport control. It’s like Global Entry but with none of the bureaucracy or cost. Absolute magic, I’m so surprised more people aren’t using it.