Mario Kart Tour has a few different things you can do for a speed boost to gain an advantage over your opponents. Aside from regular drift boosting, you can use something called Slipstream Boosting to speed yourself up a bit.
How to Slipstream Boost in Mario Kart Tour
Slipstream boosting is easy. You need to basically trail an opponent from behind, following in their path closely. The wind tunnel from their car creates a path behind them creating a slipstream, which will grant you a nice speed burst and allow you to knock them to the side.
You will know you’ve done a slipstream because an effect will show up beside you after a few second, and you will speed up and knock your opponent out of the way.
This neat little trick is also part of a few challenges, like the “Do a total of 5 Slipstream Boosts”. Unlocking these challenges grant you rewards like rubies, coins, and stars.