Cannon control building. Spoiler

4kidsandacatdog wrote:
I got the 5th daily prize of cogs right out of the box on downloading the phase 2 update, long before I received the cannon. It evidently did not save in my inventory because my cannon is not upgraded as far as I can tell. How can you see whether your cannon upgrades? Do you get a popup or is it like upgrading the board with nail from THOH?

you probably conserve them for when you get the Cannon Control Building, necessary for checking and levelling up your cannon