I once found my phone buried in the sand on a beach with no coverage. I had a year worth of pictures on it, so I stewed in anguish for almost a day until we thought about installing a Bluetooth signal monitor on a friend’s phone . Given the sluggish update frequency, we resorted to triangulating the phone’s position. As we were pulling it from its sandy grave, I swear it felt like we were cheating fate itself.
How to find a lost phone in a no-cell-coverage camping site?
31–40 of 349 posts
Re: How to find a lost phone in a no-cell-coverage camping site?
#32Re: How to find a lost phone in a no-cell-coverage camping site?
#33I thought "find my" on newer iphones could do local non-cellular location services, like airtags.
They can, but the AirTag has to be "seen" by another connected device and that device must relay the GPS position it was "seen" at. I don't know if Apple IOS is correct enough to log the time and position of AirTags when the device itself is disconnected from a network...
It’ll show up in Find My even if it can’t connect to the internet. BLE and UWB both work offline.
Re: How to find a lost phone in a no-cell-coverage camping site?
#34I once found my phone buried in the sand on a beach with no coverage. I had a year worth of pictures on it, so I stewed in anguish for almost a day until we thought about installing a Bluetooth signal monitor on a friend’s phone . Given the sluggish update frequency, we resorted to triangulating the phone’s position. As we were pulling it from its sandy grave, I swear it felt like we were cheating fate itself.
I recovered a lost device (satellite messenger in my case) via Bluetooth as well! It had just fallen into some ferns a meter or so off the trail, but without Bluetooth I'm sure I'd have never found it again.
Re: How to find a lost phone in a no-cell-coverage camping site?
#35Earlier quoted context omitted.
Obivously using certificates and TOFU. APs would share the certificate. (That's how it should work, not how it does in practice)
I’ve always wondered how commonly black hats clone and exploit mass deployed public SSIDs like the “xfinitywifi” network you see in all major US cities with xfinity. Presumably you could get a lot of random devices to automatically connect and then hijack DNS to cause trouble.
At least 50% of such APs I ran across didn’t work right. I chalk it up to broken implementation on the ISP side, but a decent number may be issues like this.
Re: How to find a lost phone in a no-cell-coverage camping site?
#36not directly relevant, but was riding my motorcycle in the boonies, and lost the phone which was on the handlebar (bumpy rocky path). Looked for it several times on the path with no luck. Then I remembered my old iPhone was in the backpack. Did a Find my phone on the backup phone and it showed exactly where it had lost touch with the primary phone. This is all without cell or Wi-Fi service. Saved me a $1000.
Oh, wow, I didn't realize "Find my" worked even when both devices are offline! But it makes sense – all that's really needed is GPS and Bluetooth.
Were you able to access it right there without signal, or did you need to move to an area with coverage for it to sync?
Re: How to find a lost phone in a no-cell-coverage camping site?
#37I once found my phone buried in the sand on a beach with no coverage. I had a year worth of pictures on it, so I stewed in anguish for almost a day until we thought about installing a Bluetooth signal monitor on a friend’s phone . Given the sluggish update frequency, we resorted to triangulating the phone’s position. As we were pulling it from its sandy grave, I swear it felt like we were cheating fate itself.
Not to nitpick but I think you mean trilaterate ;)
Re: How to find a lost phone in a no-cell-coverage camping site?
#38I wonder how cheap and low power we could make tracking beacons if we didn't actually have to send any data and could accept some privacy risk. Imagine like, an airtag, but the ID only needs to be 1 byte long, or even just a simple presence signal. You'd put it on everything you own that's portable and easy to lose. When you want to find it you just search for signals. Maybe it could have an NFC silencing feature. Pe…
> Imagine like, an airtag, but the ID only needs to be 1 byte long,
Well, then you could only ever track 255 different tags :)
AirTags are already pretty minimal. Their battery lasts about a year, and I imagine an open source equivalent should be possible to build for under $5.
This is purely guesstimated based on the fact that I have a couple of Bluetooth LE thermometer/hygrometers that cost me about $3 a piece that last about a year on the same battery (CR2032) – and these run custom firmware and need to run a display and data logger (to on-chip flash) as well!
Re: How to find a lost phone in a no-cell-coverage camping site?
#39Ha, last winter I lost my phone while snowboarding in the last 300-500m before mountain base. I noticed because I was listening to music with my airpods when I got to the bottom the music had gone silent. Thankfully I had my Apple watch with me, so I immediately got off the board and start running uphill while incessantly spamming the "ping my phone" button. At some point I saw in the watch screen it briefly connected and then immediately disconnected again. I realized somebody had probably grabbed it and skied by me. I went back running to the chairlift while still spamming the button and finally found the person who had grabbed it, a few seconds before he got into the chairlift. I felt that day that the watch investment had been worth it hah.
Re: How to find a lost phone in a no-cell-coverage camping site?
#40I once found my phone buried in the sand on a beach with no coverage. I had a year worth of pictures on it, so I stewed in anguish for almost a day until we thought about installing a Bluetooth signal monitor on a friend’s phone . Given the sluggish update frequency, we resorted to triangulating the phone’s position. As we were pulling it from its sandy grave, I swear it felt like we were cheating fate itself.
Not to nitpick but I think you mean trilaterate ;)
If we're being nitpicky it was probably neither – multilateration requires taking multiple measurements, drawing circles/lines of equal signal strength (or timing advance) and then intersecting these.
If you just want to home in on a transmitter, there's a much simpler algorithm: Try walking into various directions and keep heading into the one that makes the signal strength nunber go up :) Not sure if there's a name for that.