Which phone do I have? Type the model number.

Open Settings → General → About. The Model Number line shows a part number like MTUV3X/A — tap it once and it changes to the model number, which starts with A (for example A3106). On iPhone 8 and older it is also printed on the back of the phone.

Same place as an iPhone: Settings → General → About, then tap the Model Number line once to switch from the part number to the A number (for example A2836). On most iPads it is also printed in small type on the back. Wi-Fi and Wi-Fi + Cellular versions of the same iPad have different numbers but take the same cases.

Open Settings → About phone. The Model number line shows something like SM-S921B/DS. The letter after the digits is the region (B is the international version sold in Australia) and /DS means dual SIM. The first part, SM-S921, is what identifies the phone: a Galaxy S24.

Apple sells the same model number in Australia as in most other countries, listed on its site as “other countries and regions”. For example the iPhone 15 Pro Max is A3106 in Australia and A2849 in the United States. Both take the same cases and screens; the differences are mostly SIM, 5G bands and, in the US, no physical SIM tray.

Cases, screen protectors and replacement parts are made for one exact model. An iPhone 15 and a 15 Pro look alike but their cameras and sizes differ, so the wrong case won’t fit. Knowing the model before you buy or book a repair saves a return trip.