[threepio]

What are the practical ramifications of Apple harnessing every existing iPhone as an AirTag discovery device in the Find My network? (I think it's awful from a privacy and device-ownership standpoint, but let's leave that aside.)

For instance, because physics is real, it must take some amount of battery power & data transfer to collect information about nearby AirTags. Suppose I walk into Disneyland on a summer weekend with an iPhone. The place is going to be full of AirTags. Assumedly my iPhone will be very busy reporting on their location. Hour by hour, how does that workload compare to the stuff I ask my phone to do for me (e.g., receive text messages, download mail)? Will it run down the battery / chew up bandwidth caps in any significant way?

[mirths]

The AirTag transmits every 2 seconds. The iPhone should scan every 2 minutes for 2 seconds in order to capture the AirTag. BLE scanning costs about ~20mW. So the average power consumption is 20mW * (2sec / 120sec) = 0.3mW.

Over an entire day, it's 7mWh. The iPhone 12 battery is 10000mWh.

Conclusion: it's neglibile.

[beiller]

Would it be more if we consider the radio boot time to send a tx, and the amount of bytes sent to apples server? Also what happens if I'm at the air port with 100 air tags in range? I know they try to piggy back the data transmissions but now we are counting on apple's software having no bugs.

[Andrew_nenakhov]

Reporting this data home also costs power.

It's rather pathetic how Apple restricts user's right to use full capabilities of their devices (like restricting running apps in the background) to 'increase their battery life' while simultaneously be perfectly fine to use that power for their own benefit.

I wonder can a user disable this airtag reporting feature if he doesn't own a single airtag and doesn't want to participate in this surveillance network?

[knolan]

You can disable it from the Find My settings for iCloud in your phone.

[saagarjha]

Limiting background execution is annoying, but I'm not sure if you understand how much battery an app running in the background can consume when compared to something like this.

[Andrew_nenakhov]

I am not so sure you understand how well I am aware.

[GeorgeTirebiter]

It's the principle: other people's tags get to commandeer resources from 'my phone' without me giving permission. Unless somewhere in the iPhone fine print it say something like "by using an iPhone, you are implicitly agreeing to become part of Apple's Global BLE Network" --- well, if not that, I'm not sure how Apple gets away with this.

[ylk]

> Any iOS, iPadOS or macOS device with “offline finding” enabled in Find My settings can act as a “finder device”.

https://support.apple.com/en-nz/guide/security/sec6cbc80fd0/...

Open the Settings app and search for "Find My". You'll find the setting. Or follow this: Settings->Apple ID->Find My->Find My iPhone->Find My network

There's some explanation as to what it does and you'll be able to opt out if you don't like it. (Though you won't even see the "Find My network" setting if you had "Find My" disabled anyway)

[AlphaSite]

It also helps find your phone if you loose it. So everyone wins.

[GeorgeTirebiter]

Yes, and... you are 'automatically opted in' and you have to disable this if you do not want to opt in via Settings->Apple ID->Find My->Find My iPhone->Find My network (That is pretty darn buried IMHO, but not germaine).

I'm actually quite shocked folks on here do not appreciate that the 'default' is opted-in, rather than not. When you own an Apple iPhone or iPad, you are part of Apple's network, and some of 'your' product is used to be in service of Apple's services. It's not like the requests to send 'user data' back to an app provider 'to help improve the experience' --- it's you Will send data back to Apple because that is the default -- and most people will surely not know the Settings->Apple ID->Find My->Find My iPhone->Find My network seequence.

Does this not seem somewhat fascistic? For the record, I have 2 iPads, and also for the record, I'm an Apple alum -- I have nothing but goodwill for the Company, however, this seems, to me, quite shady. (Downvoters, I'm expressing an opinion. Not polluting HN's polite discourse.)

[ylk]

> Communication with the Find My network is end-to-end encrypted so that only the owner of a device has access to its location data, and no one, including Apple, knows the identity or location of any device that helped find it.

https://www.apple.com/newsroom/2021/04/apple-introduces-airt...

In case you care about details: https://support.apple.com/en-nz/guide/security/sec60fd770ba/... https://support.apple.com/en-nz/guide/security/secd4ab33e5c/...

I'm not sure how the e2ee works out when using Find My in the browser, but that's a different topic, I guess.

edit:

> This entire interaction is end-to-end encrypted, anonymous, and designed to be battery and data efficient, so there is minimal impact on battery life mobile data plan usage and user privacy is protected.

https://support.apple.com/en-nz/guide/security/sec6cbc80fd0/...

[vlovich123]

Are the iPhones always tracking and reporting? Or are they just watching passively for the devices reported lost and only reporting the location to Apple of your own AirTags. The latter seems far more sensible. The battery cost of this is fairly trivial. Your phone is already capturing its location and reporting for FindMy. The incremental cost of attaching the AirTag’s location is minimal. To monitor BLE for a bunch of addresses is also minimal cost that’s typically predominantly done within the BT chip to avoid waking the SoC. At first glance there are some details that are unclear here in terms of how they scale this. For example, at Apple scale, the total size of lost AirTags is quite large, larger than what you can typically offload to a BLE chip. Similarly, the privacy protection features mean that BLE addresses rotate so just passively scanning wouldn’t be sufficient. My bet though is that that’s the work that was done - offloading all of this to the BLE chip in ways that are friendly to the HW capabilities. It’s also entirely possible they worked with their BT supplier to add the necessary low-level hooks to make that perform well and preserve privacy.

[knolan]

I would say those AirTags will be with the iPhones of their respective owners. Mine report as “With you” so perhaps they don’t advertise themselves in this state. The phone will be frequently updating its own location to Find My anyway so no extra power draw.

However if you’re walking by a set of left luggage lockers or through some similar environment where lots of AirTags not with their owner then there would indeed be some overhead. If you work in baggage handling in an airport would probably be telling. This all depends on the frequency which the AirTag reports itself and the frequency where your iPhone listens out. I suspect the impact would be negligible considering the power draw of the U1 in the AirTag is of order the power draw that the phone must commit.

[threepio]

> Mine report as “With you” so perhaps they don’t advertise themselves in this state.

So you know for certain that AirTags have multiple broadcast states (e.g., "with me" vs. not)? Apple's description makes it sound like they only have one state:

"Your AirTag sends out a secure Bluetooth signal that can be detected by nearby devices in the Find My network." [1]

[1] https://www.apple.com/airtag/

[reasonabl_human]

The air tag just broadcasts location, the ‘with you’ state is generated within Find My iPhone, recognizing that the airbag is in the same location as your phone. That, and signal strength for locating the device.

[audunw]

I’m assuming AirTags just send out Bluetooth advertising packets. Your phone is continuously listening for those anyway to detect devices you own, like your watch and headphone. So that part is “free”.

The power required to process the packet is negligible.

Sending the data back to Apple could be more significant. But I guess that’s only of the AirTag is “lost”, and probably as part of a bundle of data sent regularly anyway, probably when asking Apple servers about new notifications. What takes power is waking up from sleep to send data. If the CPU is already awake, taking a few extra microseconds to transmit a few more bytes of data is nothing.

So really, I don’t think the energy and data it’s using is anything to be concerned about. It’s a drop in the bucket.

[Someone]

> Sending the data back to Apple could be more significant. But I guess that’s only of the AirTag is “lost”

To do that, your phone has to know which AirTags are lost.

A solution might be that Apple periodically sends a list of lost AirTags to phones (possibly as a bloom filter or other inexact, but compact, structure), but I’m not convinced it does. Maybe, it bets on AirTags being rare enough (who’s going to buy tens of them? I wouldn’t, as the idea of having to replace those batteries would put me of buying many) for this not to be a problem.

[cprecioso]

At first glance, I'd say the resource consumption is actually going to be basically negligible. The Bluetooth and GPS radios would probably be on anyway, and the packets flow through the air anyway, so just making a note of the IDs you see, batching them, and sending that every hour or so, is not going to be very heavy.

[BoorishBears]

> I think it's awful from a privacy and device-ownership standpoint, but let's leave that aside.

Why is that so?