letter lunch box / luch box

In modern society,young parents are suffering to raise their own childern, so they usually ask daycare houses to take care of the kids while they both are at work.
The parents can write a caring memo on the food tray to show them love.
The tray can be heated up by connecting the cellphone to the tray.
The tray is made out of rubber so it wont be slippery. The silverware and the marker will be in the tray.