The only thing [better than a PLB](https://travel.stackexchange.com/a/144195/2509) is a satellite phone, of course in combination with GPS. Only Iridium has global coverage. Forget about regular mobile phones: mobile phones only have coverage where many people live or visit. You might have coverage elsewhere, or you might not. Do not rely on them. Some people even leave their mobile phone switched on when in nature, which of course means it will run out of battery (in particular if using GPS, camera, data, tracking apps) and cannot be suitable as an emergency device. The major advantage of a satellite phone is that you can talk. When you're in a crevasse and lucky enough to still have signal, describing the details of your precise location can save your life ("I fell into the long crevasse with the oddly shaped rock near the lower end"). With poor multipath reception GPS location may be easily be 30 metre off (as opposed to 2–3 metre with good reception), and if emergency services have to explore all crevasses in a 30 metre radius, that is not helpful. Not knowing where you are is, of course, deadly. Bring a modern handheld GPS device. A good Iridium satellite phone is expensive (well over €1000 for the device), and owning one is uneconomical for most ordinary users. When I go to remote places, I rent a satellite phone. Prices may be in the order of 5–10 €, $, or £ per day, perhaps twice the cost of renting a PLB.