A few years ago I was driving around, using Google Maps on my phone as I usually do, in a smallish city, and it suddenly started showing me in the wrong position. It was like the GPS had been offset by a block or two, and the software was trying to snap my position to the streets but getting very confused because I wasn't actually there. It didn't last long, and it hasn't recurred, but I still wonder what happened and at what level in the technology stack.
Seems perfectly plausibile to be a manipulation. SDR+beamforming. The end of GPS as we know it.