There are two areas you can upgrade. The first will increase the spinning speed of your hand spinner, which means it can spin faster in the same amount of time. The second area affects the duration of a spin. You basically grease the spinners ball-bearing so that it will spin more freely and for a longer period of tim hand spinner, DIY, 3D game, speed, duration, physics, Unity3D, arcade, casual, customization, game mechanics, hand mechanic, spinning, ball bearing, upgrade, 3D, action, adventure, funny, hypercasual, space