To use WeddingHappy on another Apple device, please create an account.
You may be using a guest account. To see if you are using a guest account, go to the More tab. If there is a section to create an account, please do so. Make note of the email and password.
Download WeddingHappy on your other device.
Tap the green Log in button from the Welcome screen.
Log in with your email and password that you set up on your other device. You should then see all your plans on the second device.
Please Note: These instructions apply to v3.x of WeddingHappy. If you are not running a 3.x version, please go to the App Store and update to the latest version now.