For the readers that don’t realize exactly how old school, Sam & Fuzzy has been around since the dialup era.
It’s been through just about every phase a comic can go through, he used to write decade-long story arcs, lately he seems to be enjoying drawing simple cute dog comics. I suppose a guy needs a break sometimes from a career like that!
Without compromised hardware even igniting a battery is pretty implausible (unless the phone was on charge, and obviously these weren’t) as you’d need to basically short it out and this would be hard even with full bare metal access.
Pagers are famously hard to hack as well since all they do is display strings. And they aren’t on the public net, they don’t even have IP addresses as they communicate hub and spoke with a big slow RF transceiver.
Much more likely triggered by a message or long time fuse.