Storage: As the speed of the drill increases, the storage fills up faster. The larger the storage, the less frequently you'll need to collect Pixel tokens.
Drill: The higher the drill level, the faster you mine Pixel tokens. (Remember that by upgrading the drill, the time for collecting decreases, as the storage holds a certain number of pixels at different levels!)
Referral Storage: This is where the tokens mined by your friends as your referral bonus are stored. You need to collect them as it fills up.
