What you need:

The game save (File below)
Diskaid (File below)

Tutorial~

1. Download Diskaid, launch the program.
2. Plug your iOS device into your computer.
3. You will see a drop down menu on the left showing all your apps, games, etc..
4. Download the Temple Run 2 save I posted below.
5. Drag the game save right into the colum, once you do that it will ask if you're sure you want to overwrite click "Yes".
6. Unplug your device from your computer.

This save comes with 99,999,999 Coins & Gems

Temple Run 2 Modded save (Mega)
Temple Run 2 Modded save (Mediafire)
Diskaid

Tch I do not have that shit (IOS) @ I have the first one.

The 2nd one is better.

@Added Mega link.