I’m not a lawyer, but I don’t think “Donating your assets” would work (in any jurisdiction, but as I said, I’m not a lawyer, certainly not one versed in law in all countries of the world). Lawyers will argue that the fact that you set this up x months before death doesn’t mean that you still wanted it to happen when you died and/or that, at the time the assets were transferred you weren’t alive, so you couldn’t own the assets.

Yes, last wills do both, too, but they have a long history with lots of jurisprudence about what you can and cannot arrange for after you die, and how you should arrange that (https://en.wikipedia.org/wiki/Will_and_testament#Requirement...)

There's a chain of problems here. You'd need an open source GPS tracking app on your phone that has the rights to record and upload your location to a server whilst running in the background, then you need a personal server to store that stuff on, and then you need to find someone who knows what to do with that lot if and when you disappear.

No, clearly whoever kidnaps you is going to take your phone away. I mean something that probably gets embedded under your skin somewhere.