There are various objects you can collect during game play to get boosts. They provide a temporary speed boost, and also fill the boost meter to also allow manual speed-ups. When you see a boost pad, take the time to hit them as quickly as possible to shorten your completion time. When in a boost, extra effort will be required to steer your dog. Do this by tapping instead of holding the screen.

Chevrons: Boost your speed.
Force fields: Send you in the direction that they are pointing and speed you up.