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Comment by ShakataGaNai | Hacker News Reader

The problem I see with this is that your phone always has to be broadcasting the BLE beacon, regardless of if it is lost or not. Otherwise it could randomly end up lost in a place with poor/no service... and would never be found

For phones, how often is this really an issue? Sure, this is useful for the Tile type "dumb" devices... but if my phone has no cell or data service... it's probably because the battery is dead.

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Some people have hypothesized that this isn't necessarily for finding phones. This might be about using phones (and iPads, Apple Watches, MacBooks, etc.) to create a network like the one used by the Tile product for finding wallets, keys, etc. This could be a product Apple unveils in September.

This is for tracking lost MacBooks. Apple said this at the keynote. They may expand it beyond laptops, but that's the initial scenario. (It's a great one.)

Complete speculation here, but I wouldn't be surprised if devices could keep broadcasting the ping after they're "dead". Tiles last for years without charging, so I bet if Apple can leave on only the bluetooth beacon after the battery drains past where it can power the rest of the phone then this would be doable.

Again complete speculation, I have zero clue if the current hardware is even capable of doing this.

The current hardware might not be, but you could run this on a secondary chip similar in specs to the T2 or Secure Enclave. You could theoretically even have a second battery specifically for this purpose, but that would likely be cost-prohibitive.

The T2 chip is a derivative of the A10. It has similar power requirements to the SOC in modern iPhones.

They could probably use a cut down derivative of the W2 chip used in AirPods with the audio codec etc. removed. I’m guessing phone batteries reach a point where they’re still storing energy but can’t provide enough current to safely boot the whole phone. The BLE chip could sip on the remainder of the battery for a long time.

That sounds reasonable. I had no idea the T2 was that powerful.

It's also the SSD controller, and quite impressive in that regard.

I bet the T3, whenever that arrives, will be a derivative of the A12 or A13, and provide the neural network accelerator to MacOS and CoreML.

This would be excellent. I'm hesitant about the prospect of an ARM based macbook, but having both seems mighty compelling. As a lower power application CPU for light usage, or a full x86 with accelerators / co-processors when needed.

recent apple phones have NFC, which cannot be disabled.

Can NFC be used by iOS applications, e.g. SSH authentication via smartcard, where the private key never leaves the card?

I think it is possible in iOS 13, unless I misread the WWDC video description.

Not at the moment, but one element suggesting it will be in iOS 13 is that the UK Home Office announced their app for validating European passports (which uses NFC but only on Android at the moment) will be able to work on Apple devices at the end of this year - basically when iOS 13 will be released.

Also, couldn't the BLE beacon be used by "smash and grab" thieves to find devices in your car?

Yes, and this is already happening due to the feature that Macbooks have to connect to eg. BL keyboards and mouses. Perhaps also the "Smart Sleep" function (not sure what it's called exactly) that periodically connects to Wifi to fetch emails so they're there when you open your Mac again. This has happened to me and other folks here in NL, by the way.

Given how little power it takes to operate something like a Tile, maybe the beacon will continue operating for quite a while after the battery is too low to operate the whole phone.

I can think of several scenarios:

* I lost the phone hiking somewhere with no signal

* I lost the phone / it was stolen while in airplane mode

* I lost the phone while traveling abroad without any local service

This finding service will work for wifi-only ipads, wifi-only apple watches, and macbooks in addition to the likely tracking tokens.

Stolen while in airplane mode, and you're going to rely on BLE? A "good" thief would learn that he'd need to carry around a Faraday cage (read: some tinfoil) to block the signals. The only disadvantage is that the act of putting tinfoil around an iPhone then becomes suspicious.

They'd just have a tinfoil lined bag. No suspicion. I bet you can buy one one Amazon for next to nothing as it is.

Someone could wrap a phone in tinfoil pretty quickly or have one ready-made in the shape of a pouch. Or start carrying a special pouch that stops signals.[0]

Either way once you remove the phone from sight, the suspicion is probably over. The only next step is to kill the signal.

[0] https://www.overyondr.com/howitworks

> (read: some tinfoil)

Try it. Wrap your phone in tinfoil then call it. It will still ring.

It's harder than it looks to make a Faraday cage.

Apple is highly averse to having your phone send out any BLE beacon all the time. Likely what they will do is the following:

1) The iPhone will be considered the "master" (aka BLE Central device)

2) All of your devices that you enroll in your "find my" service will be required to sending out a periodic BLE beacon or a similar bluetooth packet (BLE peripheral device)

3) The iPhone will periodically listen for BLE beacons and upon receiving that beacon it has 3 options:

->option 1, save the time/location when it saw that beacon

->option 2, scan the device with a BLE "scan request" operation which asks the device to provide more information -- it provides the "scan response" packet which can and often is different from the main advertisement packet

->option 3, connect to the device and query further information like your macbook battery level and maybe other info

For option 1, the iPhone never needs to send a packet ever and will simply have its BLE RX radio stage on listening for advertisement packets -- which are sent in clear text for anybody to listen to. The RX stage is listening periodically and works on a statistical basis where if the beacon side is transmitting very rarely then you can easily miss the beacon.

So.. what you should take away from this is that highly likely Apple will only allow the iPhone to be the master and all of your other devices will be periodically sending out beacons. So if you have this enabled and you walk around with your iPad Pro and your iPhone together and people sniff bluetooth packets, they can track when you walk down the sidewalk past you every day. For example if you live near a busy street in New York or something, start sniffing for bluetooth packets and you'll find tons of stuff. Tons.. most of it is random bluetooth headphones, but pretty soon it will be iPad Pro's.

> your phone always has to be broadcasting the BLE beacon, regardless of if it is lost or not

It could have an X-hour "deadman timer" after which if it still hasn't successfully phoned home and been told it's not lost, it starts pinging?

Don’t think phone. In the keynote I think they showed it with a Mac, which isn’t available with cell service. Or as someone else mentioned maybe you have an iPad without cellular.

It would be useful for those.

Fair point. For wifi only devices, I could see it having some use.

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