Curious how Yellowbox works? It’s easy. Open the app. Book a locker. Unlock & store your things. • Find and open a locker through the Yellowbox app. • You can open up your locker via the app and store your belongings. • When you are finished with your use, open the locker with the app, and then End your booking in the app. Want to store your phone? At most of our locations, you can set a 4-digit pinpad code in the app, which can be used to unlock your locker without your phone.