On Yay! you can transfer your account when you change devices or uninstall the app by saving your account.
■How to save (For iOS and Android)
1. Tap the Settings icon at the top right of the profile page
2. Tap the account name
3. Tap Account information
4. Tap Save current account
Also, if you have already saved your account, you can check your Account information through the following steps.
1. Tap the Settings icon at the top right of the profile page
2. Tap the account name
3. Tap Account information
4. Tap Login information
