Speaking of blind faith in technology...
About ten or fifteen years ago three guys were doing a loop in Kings Canyon NP. For those familiar with the area, they went in at Roads End and did a loop southward. On their return to the trailhead, as they were passing through Sugarloaf Valley, they were considering the trail back to their car. The maintained trail went 3000' up and over Avalanche Pass, and then looped around to drop 5000' to Roads End. One of the guys consulted his GPS, which told him that they could cut a number of miles off their trip as well as 3000' vertical if they just went north from Sugarloaf, along Roaring River, to get to Roads End. What anyone with a topo map would quickly see is the reason the trail didn't go that way - Roaring river descends an ever-steepening drainage before dropping down a 2000' vertical cliff. These guys blindly followed their GPS. As the drainage got steeper and steeper, and the river more and more whitewater, they had to cross multiple times, and one of the three guys lost his pack while crossing the river. And then they got to the 2000' cliff. And right then an early winter storm (this happened in October) dropped three feet of snow that night, on three guys who only had gear for two people. I don't think it was a fun night for them. Fortunately for them, their position on the rim of the canyon made them easy to spot from the SAR helicopter, and they got airlifted out. Not only did they blindly trust their GPS, they didn't have the sense to at least look at a topo map to make sure, or perhaps they didn't even have a topo map with them. And another blunder was to go into the high country without checking the forecast, which would have warned them about the coming storm. I have spent enough time in the Sierra high country to know that if there is a winter storm on the way, you had better bring good winter gear and be ready for a lot of fresh snow. Three feet from one storm is quite common, and I have seen storms dump ten feet.
That is the story I usually tell people who place too much faith in electronic devices. I would rather trust a topo map and compass.