Don’t take your cell phone when you’re joining a riot. Or if you do get caught up in a riot, take out the batteries.
just dont own a cell phone
Steal a government official's cell phone and take it to the riot. Leave it on. Respond to the text with threats. Return it to the official's office/home later.
An aluminized Mylar bag might make a good cell phone accessory. Batteries aren’t removable from many.