Why was physical SIM only dropped in the US?
To give advance warning to carriers outside the US that it won't be before too long until all iPhone models worldwide are eSIM only.
More specifically, the piss poor operational security of US carriers lends itself quite well to make the US the harbinger of the death of physical SIMs.
Most in carriers the US will happily send you a SIM card by mail without any need for ID. In fact, most carriers in the US will just as happily have you read them the ICCID (a.k.a SIM card number) on a SIM card you already have and activate your line on it.
This is pretty much unheard of overseas, where you either have to pick up a SIM card at the store and ID yourself or have one delivered to you by a courier who will check your ID and scan it in with a portable scanner.
Using a SIM card that you had laying around in the drawer is entirely out of the question.
On the flip side, overseas they mostly couldn't care less which device you activate on the line (i.e. which IMEI is active), whereas in the US some carriers either block unrecognized IMEIs or, such as AT&T, activate capabilities on the line based on the IMEI they expect to use the line.
eSIM however, is pretty much designed to mimic this American laissez-faire approach to SIM activation. Your phone essentially has a SIM card built in and in the settings you can find its ICCID.
In short, eSIMs provide three main ways of activating service.
Either you provide your carrier with your phone's ICCID, your carrier can then activate service on that ICCID, similar to how they would do it if you'd provide them with a physical SIM's ICCID or you can scan a carrier provided QR code, which basically contains an encryption key and some information for the carrier's backend to recognize who you are to accept your phone's ICCID to activate a line on.
You can also initiate activation entirely from your iPhone and then log into your cellular account, after which the above basically happens in the background.
There are some other varieties of enabling an eSIM or sometimes they are combined, but that's the gist of it.
In theory, with eSIM, you can just go into your iPhone's settings and easily transfer a line by logging into your carrier account or purchase a new line as a new customer. Even hop around from carrier to carrier depending on your needs in a particular situation.
And I've witnessed this ideal approach firsthand when purchasing data plans for my iPad, in particular abroad.
In practice, some carriers, although few, like to put up hurdles by requiring verification or requiring you to get in touch with them over the phone.
When I break my phone and can no longer turn it on, what is involved in getting my standby phone up and running with the same SIM so I can receive calls?
The amount of steps is a bit dependent on your carrier, but the major US carriers support what Apple calls eSIM Quick Transfer.
In that case it's extremely simple and you don't have to contact your carrier.
Steps as follows:
- Connect your backup iPhone to Wifi and make sure it's logged into the same Apple ID
- Go to Settings
- Tap on Cellular
- Tap on Add Cellular Plan or Add eSIM
- Tap on your number in the "Choose a Phone Number" screen
- Confirm
- Done
If your carrier doesn't support this, then step 5 would be to use a QR Code, for which you need to contact your carrier. If you don't have another device to display the QR code on then there's an option to enter the details (i.e. SM-DP+ Address, Activation Code and, if provided, Confirmation Code) manually.
In my experience T-Mobile likes to provide these codes for you to enter manually, whereas AT&T strongly prefers providing you with a QR code.
In any case, this seems to be a shot across the bow aimed at carriers outside the US.