The factory is a place which is unlocked at level 6. You can use the factory to upgrade items so that you can decrease delivery time and increase revenue and stock, at the cost of certain materials or money.
These are delivery comparison.
|Basic Item||1st Upgrade||2nd Upgrade||3rd Upgrade||Fully Upgraded|
|2mn||1mn 40s||1mn 20s||1mn||40s|
|3mn||2mn 30s||2mn||1mn 30s||1mn|
|2hr||1hr 40mn||1hr 20mn||1hr||40mn|