Something that Sony was showcasing a couple of years ago is a bit on that line, although more radical: create a pre-initialised image to load at boot, just like if the device was doing a restore after a suspend-to-disk.

This works well for something like a camera where the set of apps to have running when powering on is well known and limited.

However there could be some hybrid implementation where the basic system is saved in the image and a list of running apps is saved before switching off.

But i still stand for my point that one should _very_seldom_ have to reboot/power_on.