I have non-disposable heaters for my toes. And non-disposable hand heater to last all day. The last one has lasted forty years and is ready for a lighter fluid charge this year.
As for hand coverings, I opt for mittens. My mittens have a covering for the trigger finger. I'm all set for cold weather. Don't have to take them off to shoot.

Flags, I take my flip phone which is turned off in case something happens. Nature doesn't bore me trust me. I put in 643 hours in my stand last year and I am going to break that record this year. I have missed one day of our season here in 17 years and counting.

I never use hand warmers or toe warmers. Because of my daily ice fishing for panfish my hands are pretty tolerant to the cold. I use a lite weight pair of cotton gloves while hunting that is it.

Frostbite? ...More like an Ice Tan! I don't have problems with my hands getting cold. My feet get cold if they are wet though. As long as I can keep my boots dry I stay pretty comfortable. It probably helps that I primarily hunt from the ground, especially when it's cold, and I do allot of still hunting....
-Jake

Many in our hunt club use texting to contact other hunters instead of walkie talkies and other device. Placed on vibrate they work better than many of the radios out there. Each to his own and safety includes being able to contact others in an emergency. Use what is available to your benefit.

I got my 2 hand warmers Friday and had them in the woods this weekend. Very impressed so far.