Karaoke Sync™

Not directly. The iPhone app and the Android app are sold through two separate stores — Apple's App Store and Google Play — and each store handles its own billing. The two stores don't share purchase information, so a Pro subscription bought on one platform can't be detected, restored, or transferred to the other. Karaoke Sync doesn't use a sign-in account, so your Pro access is tied to the store you purchased through. Your subscription stays active on the device where you bought it. If you'd like Pro on a device that uses the other store, you'd start a subscription within that device's app. This is how Apple's and Google's billing systems work for most apps that don't have their own login accounts — it isn't specific to Karaoke Sync.

Your current subscription keeps working on your original phone for as long as it's active. On your new phone, Pro is a separate purchase through that phone's app store. If you no longer want the original subscription, cancel it so you aren't billed on both:

• Cancel an Apple (iPhone) subscription: on the iPhone, open Settings, tap your name at the top, tap Subscriptions, choose Karaoke Sync, and cancel.
• Cancel a Google Play (Android) subscription: open the Google Play Store app, tap your profile icon, tap Payments & subscriptions, then Subscriptions, choose Karaoke Sync, and cancel.

"Restore Purchases" only looks up purchases made through the store you're currently on, using that device's store account — Google Play on Android, the App Store on iPhone. If you bought Pro on a different platform, Restore won't find it, because that purchase lives in the other store. Restore is for getting your subscription back on the same platform after reinstalling the app or moving to a new device that uses the same store account.