Rule of thumb: anything that is not a natural object, or made by hand, incorporates wireless and is therefore a device by the matrix rules.
Your guns, your armor, your socks, everything is a device. Even if it doesn't have wireless bonuses, it can still be tracked via the matrix, and hacked to some degree. For example, even your bowl of Ramen soup can potentially be hacked so that the nano-flavor enhancers broadcast rotten eggs to your DNI or olfactory/taste cyberware. Of course if you're not accepting simsense input from your food, hacking your food has very limited impact on you.
By default everything just exists out there on its own, but in practice anything that's supposed to have some modicum of security should be protected by a host or a PAN.
Device rating guidelines didn't make it into the 6e CRB, unfortunately. But there's no reason you couldn't use 5e's:
DR 1: Expendable, cheap, or single use consumer goods (cans of Dragon Piss, light bulbs, etc)
DR 2: Most consumer goods (Soykaf Makers, your trideo unit, etc)
DR 3: Security goods (cameras, maglocks, traffic lights, etc)
DR 4: Stuff made for police/corpsec use
DR 5: Stuff made for military use
DR 6+: High tech or experimental stuff