Upgrades will help you get further in the game. Quick overview and price in games store:
Pterodactyl - Cost: 1,500 coins
The Pterodactyl power-up allows players to skip 2500m to the sunset area.
This upgrade is great if you're getting tired of running the easier early stage of the game over and over. Note that you only get one use of the Pterodactyl for each purchase you make.
Parachute - Cost: 3,500 coins
The Parachute brings back a character that has previously fallen off the raft.
If you're close to a high-score, you might want to think about calling in the Parachute upgrade. If you've lost a crew member, this upgrade will bring them floating back to the raft so you can push onwards for an even higher score.
Whale Tail - Cost: 5,000 coins
Once the round ends, the whale will whack titan an extra 1000m.
If you want to get just a little bit further on a round, activating this upgrade means your last remaining crew member will be given a mighty wallop, propelling them an extra kilometer through the jungle in the process.