Can I Transfer Game Data From Android to iOS?

Hello,

I recently upgraded my phone from an older Android model to a new iPhone. When downloading Galaxy of Heroes, I found that it automatically logged me into a new account with the Apple Game Center and gave me no option to sign in any other way. Is there any way my game data and be transfered from Google Play to the Game Center or do I have to start all over again?

Thanks very much for any help!