It’s been years but I ran into a problem with a notification extension years ago. Worked fine on simulator, not on device. Turned out it was because I was using a HEIF image and (I think) the on-device extension was trying to use hardware decoding and didn’t have access to it. Meanwhile the simulator had no such sandboxing restrictions.
The difference doesn’t matter until it does, and then it’s infuriating to work out what’s going on.
It’s been years but I ran into a problem with a notification extension years ago. Worked fine on simulator, not on device. Turned out it was because I was using a HEIF image and (I think) the on-device extension was trying to use hardware decoding and didn’t have access to it. Meanwhile the simulator had no such sandboxing restrictions.
The difference doesn’t matter until it does, and then it’s infuriating to work out what’s going on.
Last I checked, VPN network extensions wouldn't run in the simulator.