I turned off bluetooth on my iPhone so it doesn't automatically connect to Airpods yet when I opened the case near my iPhone it still managed to offer option to connect. I saw similar dynamic on iMac when I turned off bluetooth yet I would get option to connect to mouse. Is there another way than bluetooth apple uses to communicate between devices?
When you use the Control Center to "turn off Bluetooth", you're actually not turning off Bluetooth. Pressing the icon means to disconnect from any connected Bluetooth accessory. It does not disable Bluetooth entirely, and thus a feature such as detecting the Airpods case being opened will continue to work.
If you go into Settings > Bluetooth and actually turn Bluetooth off completely, you'll find that the case open detection feature stops working.
3Same applies to wifi, btw Jul 27, 2021 at 15:53
1This answer is incorrect, because the mechanism described by OP is the NFMI, and not Bluetooth. When you turn off bluetooth, the case-open detection STILL WORKS and iPhone sees the AirPods - However, it won't display this status to you. Jul 27, 2021 at 19:42
@R..GitHubSTOPHELPINGICE Yes, a similar principle applies for the WiFi button. What it means is that it disconnects you from the network(s) you're connected to right now, and it won't automatically join a AP WiFi network until certain criterias are met (i.e. for example waiting until the next morning, rebooting the phone, etc). It does not mean that the WiFi radio is turned off, and thus the phone will still do for example AWDL over WiFi for AirDropping. Jul 27, 2021 at 19:55
1@MottiShneor It doesn't use NFMI. The case sends out a Bluetooth beacon periodically with information such as the charge (0-100%) of the left/right AirPod and the case itself, whether or not each pod is in the ear, whether each pod and the case is being charged - and whether or not the case is open or closed. That's really all there is to it. Jul 27, 2021 at 20:05
First off, Apple AirPods and iPhone have more than one way to communicate.
Indeed iPhone uses Bluetooth protocol and hardware to transmit audio to the AirPods and from the AirPods microphones.
But AirPods also have a new way for short-distance data sharing called NFMI (Near Field Magnetic Induction) which is used to transmit status information when you open the lid near the iPhone.
This mechanism is so low on energy - that is is by definition always on. It is the same mechanism used for ApplePay when you place your iPhone near something you want to buy, or at the cashier when you want to pay. This is VERY reliable, does NOT rely on broadcast, and is very safe, because it is NOT bi-directional.
ApplePay uses NFC (Near-Field Communication) - NFC can enable two-way communication for certain applications. It, and the AirPod communicating with the iPhone, does not use NFMI when understood how NFMI is usually understood in this context (i.e. as in for example MiGLO for headsets - and not as a generic term encompassing all kinds of near-field magnetic induction including NFC). Jul 27, 2021 at 19:51
1Can you provide a source that Apple uses NFMI with Airpods?– sfxeditJul 27, 2021 at 19:57
It doesn't use NFMI. The case sends out a Bluetooth beacon periodically with information such as the charge (0-100%) of the left/right AirPod and the case itself, whether or not each pod is in the ear, whether each pod and the case is being charged - and whether or not the case is open or closed. That's really all there is to it. Jul 27, 2021 at 20:04