Initialisation from plugin template.

ios/Classes/AppcenterPlugin.m

@@ -0,0 +1,20 @@
+#import "AppcenterPlugin.h"
+
+@implementation AppcenterPlugin
++ (void)registerWithRegistrar:(NSObject<FlutterPluginRegistrar>*)registrar {
+  FlutterMethodChannel* channel = [FlutterMethodChannel
+      methodChannelWithName:@"appcenter"
+            binaryMessenger:[registrar messenger]];
+  AppcenterPlugin* instance = [[AppcenterPlugin alloc] init];
+  [registrar addMethodCallDelegate:instance channel:channel];
+}
+
+- (void)handleMethodCall:(FlutterMethodCall*)call result:(FlutterResult)result {
+  if ([@"getPlatformVersion" isEqualToString:call.method]) {
+    result([@"iOS " stringByAppendingString:[[UIDevice currentDevice] systemVersion]]);
+  } else {
+    result(FlutterMethodNotImplemented);
+  }
+}
+
+@end