i'm trying to get working method $ionicPlatform.isIOS, to get boolean value by the used platform where is app running. 

I tried it on Android device and In Chrome Browser, but without any success result.

```
  $scope.getDeviceInfo = function() {

        $scope.isIOS = $ionicPlatform.isIOS();
        alert($ionicPlatform.isIOS());
  }

```

Code above is returning following exception:

```
Uncaught TypeError: undefined is not a function

```

What i'm doing wrong please?