Originally Posted by javabytes

Also, with iPhone’s cellular data switching feature, Apple makes it sound like it can use both lines depending on coverage. In practice, I’ve found it seems to hold on to the primary data connection far longer than it should... I don’t know if that really means it will switch only when the primary connection has zero signal, instead of very weak signal, but that seems to be the case. Anyone else experiment with this? I’d love for the phone to more aggressively switch connections… if I have 1 bar and slow speeds on the primary line, and full signal on the secondary line, dual SIMs would be a lot more useful if it switched automatically in that circumstance.