Before you start a race, you'll be able to choose from a selection of different upgrades:
Nitrous can - This rocket fuel will give you a much quicker start to the race. Just be careful with those early jumps as you can easily spin yourself out of control.
Coin symbol - Selecting the central coin symbol will double the number of coins you earn. Nice!
Coin magnet - If you've played any endless games in the past, you'll be very familiar with this handy upgrade. With this equipped, any coins nearby will automatically flow towards you, leaving you free to concentrate on your aerial aerobatics.