plz help me.

There are three ways of saving your progress so your game can be continued across multiple devices: Facebook, Game Center, and Google Play.
 Tap the Settings icon at the top left of your screen to see your login options. 

iOS users have the option to connect through Game Center. This saves your progress with Game Center, collects Game Center achievements, and lets you visit your friends' cities. By logging in with the same Game Center account, you can transfer your game progression from one iOS device to another!

Android users have the option to connect through Google Play. This saves your progress with Google Play, collects Google Play achievements, and lets you visit your friends' cities. By logging in with the same Google Play account, you can transfer your game progression from one Android device to another!

Facebook users have the option to connect through Facebook, regardless of whether they use iOS or Android devices. Your progress is saved with your Facebook account, and we promise not to spam your wall or bombard you with invites! This login has one great advantage – with a Facebook login you can keep playing your game across both iOS and Android devices!

You can be logged in with both Game Center and Facebook simultaneously, and you will get the benefits of both accounts. In the same way, you can be logged in with both Google Play and Facebook.

It’s important to note:

• It’s only possible to build your city on one device at one time! If your game account is being played simultaneously on two different devices, you’ll see an error message and will be unable to continue. Close your game on one device to continue playing on another.
• If you’ve been playing on a new device, connecting through a social account will save your progress. 
• If you’ve been playing on a new device, connecting through a social account which already has saved data associated with it will result in the loss of any progress made on that new device. (You’ll see a confirmation message to make sure this isn’t done accidentally.) 
• If you have been playing offline on one device and start to play online on a secondary device (using the same account login), any offline progress you made on the first device will be overwritten and cannot be retrieved.

If you disconnect your Facebook account from your city or remove the permissions for SimCity BuildIt from your Facebook account, don’t worry - your game data won’t be reset! The very first time you connected your city through Facebook, a link was forged between the two. So you can log in again to Facebook anytime to catch up with what your friends are doing. The same goes for Game Center and Google Play too!

How do I visit my friends?
Once connected through Game Center, Google Play, or Facebook you can visit your friends’ cities.
 Tap the green friends icon on the left of your screen to see the profile picture, stats, and city name of each of your friends connected through the same social connection!

If you aren't connected socially or don't yet have any connected friends, you will still see your neighboring mayor, Daniel.

To visit a friend’s city, tap on their picture. Now have a look around their city to see how they’re doing, or visit their Trade Depot to see what items they might have for sale. 
 The Trade Depot appears just outside their city limits and is marked with a blue trade icon.