APK MOD INFO
Name of Game: Chelsea Runner
VERSION: 1.2.3

Name of the cheat, mod, or hack (credits: wendgames):
-Coin/Whistle/Unlocked

Chelsea Runner MOD APK 1.2.3 (Coin/Whistle/Unlocked)

Download the CACHE file/OBB file. They should be .zip or .rar files.
Extract the file to your sdcard.
Move the extracted folder to the location: /sdcard/Android/obb