The mailbox is where you receive the rewards you have earned and purchased items.
Admin[]
The Admin tab is where you receive the rewards you have acquired while playing the game.
Market[]
The Market tab is where you receive items purchased from the store.
Contents[]
Content is where you receive notifications and rewards for game content such as raids.
When a friend discovers a raid and requests help, you can go to the appropriate tab and check the help request mail.
Ads[]
This is a tab where you can watch advertisements and apply various amplifier effects for free.
It takes effect as soon as you finish watching the ad.