It's easy to restore purchased bundles, textures, or formula packs from within the app.
To get started click on the store button from the main screen:
Next you can restore all purchases by scrolling to the end of the pack thumbnails, or by clicking into an individual pack and press the "Downloaded" button at the bottom:
You'll be asked to enter your password and then you'll see this popup and then the app will start downloading your purchases again.
