You'll need the following
[ Register or Signin to view external links. ]
Your iDevice
The App
This [ Register or Signin to view external links. ]

Warning you will lose all you data in exchange for unlimited gems and coins!

Steps
1)Play a couple games, quit and then plug your iDevice into your computer

2)Open up iExplorer click on Apps in the top left corner, then Temple Run 2, click on documents and you should see gamedata text. Delete it and find the data text you just download it it and drag and drop it in where you deleted your old gamedata text

3) Go back on your iDevice and open up the kill board (Double click the home button) and press/hold on Temple Run 2 until there is a subtract sign, tap it and then open up TR2 and you should have everything.