iPhone 11 Allow Cellular Data Switching

[max2]

Does this setting work well?

How does it determine which cellular network to use for data ?

Reason I ask is because one of my plans have limited data the other unlimited.

 

[jschnee21]

No.

Cellular data switching always uses your primary data (e)SIM up until the point that there is no RF signal (aka no service) for said carrier. Then it will attempt to switch to your secondary data SIM.

If all RF signals are low, because you are underground, in an elevator, building, etc. it just bounces back and forth leaving you with no usable service.

Seemed like a good idea, tried it for a week or two, ultimately turned it off. Might work better in a rural setting where one carrier is better than another.

But in my case where buildings are the issue (school gymnasiums mostly) it was completely useless.

 

[NYCValkyrie]

No.

Cellular data switching always uses your primary data (e)SIM up until the point that there is no RF signal (aka no service) for said carrier. Then it will attempt to switch to your secondary data SIM.

If all RF signals are low, because you are underground, in an elevator, building, etc. it just bounces back and forth leaving you with no usable service.

Seemed like a good idea, tried it for a week or two, ultimately turned it off. Might work better in a rural setting where one carrier is better than another.

But in my case where buildings are the issue (school gymnasiums mostly) it was completely useless.

Small correction - it'll use whatever you set as primary under Cellular Data first, not necessarily eSIM. But it's true that it doesn't work very well.