The following is the story of how the author was able to find his cousin smartphone in the jungle, where no cell satellite was available. Spoiler: they were able to detect the phone by creating a fake WiFi network that matches the same configuration as the cousin home WiFi.

https://manas.tech/blog/2023/10/25/approaching-unconventional-problems/

A few weeks ago, I went on a trip with my dad, uncle, cousin and a couple of their friends in order to share an off-road trip on ATVs across the jungle. There were about twelve of us enjoying the landscape in Misiones, northern Argentina, with its tea, tobacco and yerba mate plantings. Not that you could expect to see lots of wild animals around those noisy ATVs.

Ready… set… go!

Largely beautiful as this country is, as you get into more rural areas, there’s a high chance you won’t have cell phone coverage there - I’ll leave it as an exercise to the reader to choose if that’s a feature or a bug.

So there we were, making an asado (think “barbeque”, if you must) in the cabins we’ve rented in the middle of nowhere, when my cousin started to look around for his phone. In the hour after the last time we knew he had the phone, he took a 50km trip to the closest town to shop for some fuel and beverages - so we really hoped he didn’t lose the phone there. We’d already called and sent some WhatsApp messages, so we knew the phone wasn’t reachable. So we checked the area around the grill, we checked the cabins, we checked around the place where we were playing some cards (yes, it had to be Truco), we checked in the truck in which he went to the town - all to no avail.

Using the “Find my device” feature of the phone wasn’t really an option, since there was no way the signal was going to reach the phone. So… was there anything else to try?

There were lots of butterflies around - but I think the pattern on this one is not actually a serial number.

It turns out - there was.

After having lived in a rural area for almost two years, I’ve learnt to save battery by switching my phone’s wifi off whenever I go into the woods or mountain - but I also know that people don’t usually do that. After confirming this assumption with him, I’ve used my own phone’s tethering feature to create a wifi network with the same name & password as my cousin’s home network - and we started walking around the place. We made sure the other guy helping us with the search had his own wifi off, to avoid false positives, and waited to find a new connection to the hotspot. And it worked! The connection was made when walking nearby the parked truck, but it turns out that the phone wasn’t in the truck - it was lying on one of the ATVs that was parked by its side.

Should we not have found it so “soon” with this strategy, we would have started walking in different ways from that zone to try to triangulate the signal - but we were lucky to not need that.

There’s that nice feeling in being able to combine your techie knowledge and the lessons learnt from constrained environments just for fun - double that when it helps to help someone solve a real problem.