I just bought a new iPad and I’m wondering if I can move Clash of Clans from the old to the new and save the progress. I spent a fair bit of money into it and I don't want to lose it.
Extracted from the Clash of Clans FAQ:
Can I continue my game on a new device?
Yes you can, but it requires the use of GameCenter. The only way to transfer your account to a new device is to have the original village linked to a Game Center account. Login to that Game Center account on your new device and you will prompted to load your previous village.
This post which requires a login, has some helpful instructions on setting up your game on a new device.
It doesn't look like you can transfer In-app purchases between devices:
Subscriptions and replenishable In-App Purchase cannot be transferred or synced to another iOS device. Non-replenishable In-App Purchases and auto-renewing subscriptions can be transferred to another iOS device authorized with your iTunes Store account. For example, if you transfer a game from an iPhone to an iPod touch, only the game levels will sync over, the extra ammo and experience points will not be transferred.
Re-downloading In-App purchases for free depends on the App:
If you lose your In-App Purchases because apps were accidentally deleted, or if you had to restore your device without a backup, you may be able to download some of your in app purchases again for free. Not all In-App Purchases are eligible for free download again.
Replenishable In-App Purchases and subscriptions cannot be downloaded again for free, and must be repurchased. Examples include but are not limited to: extra ammo, additional health, extra experience points, or other one-time services. Non-replenishable In-App Purchases and auto-renewing subscriptions can be downloaded again for free. Examples include: bonus game levels, a map/city guide, a daily news subscription, or other recurring services. To download an In-App Purchase again, you must download it from within the installed app using the same iTunes Store account name for the original In-App Purchase.