The only way to transfer your game from an iOS device to an Android device (or vice versa) is by using a Facebook account.
Here’s how you do it:
Start by connecting your game to Facebook on your iOS device. Let’s call it Device A:
1. Play Star Chef until Level 5
2. Go to ‘Chef Circle’ present at the bottom right corner of the game screen.
3. Login to Facebook
 To transfer the game to your Android Device, let’s call it Device B, first download the game on the device, and follow the steps below:
1. Play Star Chef until Level 5
2. Go to ‘Chef Circle’ present at the bottom right corner of the game screen.
3. Login to Facebook with the credentials used on Device A
 
You’ll be given the option to load your saved game once you reach. Confirm, and you’ll be ready to go! 
If you want to play the same game both on iOS and Android devices, you can only do so if your game is connected to Facebook.