Apples come in green, gold, and brown varieties. The gold apples are worth more points and rotten apples will subtract points.
Coins
Although coins do not help your overall score on a level, they can be used them to purchase power-ups and upgrades. Besides collecting them during game play, you can also get coins in the ship by viewing ads.
Easy lives
Quit the game then advance the time on your device by one hour. Resume the game and you will have regained lives. Then, set the time back to the correct value.
Movement options
Set the speed of your character to "slow", as shown by the tortoise icon. This will help you react better in tight siutations.
Survival mode
Every few levels a cloud will float above a regular level indicating the availability of Survival mode. Playing this mode will give you a chance to earn a large amount of coins and points, however it will end when an enemy is hit.
Upgrades
Upgrade the Spikes as often as possible. Each upgrade increases their duration. Killing hedgehogs with the Spikes is a good way to increase your points.
Various strategies
You usually will have a time limit for collecting coins and fruits. Tile your device harder to move faster only when there are no hedgehogs to collide with or when you have the Spikes power-up activated. Build combos by collecting items or destroying hedgehogs in sequence. Remember to avoid rotten apples.
Apples...