Brand new Xamarin Forms application with iOS platform project. Added LinkOS_Xamarin_SDK in forms project and iOS project (v1.1.75). Placed the following code in one of my page code behind:
 
sing System.Threading.Tasks;
using System.Text;
using System.Diagnostics;
using System;
using Xamarin.Forms;
using LinkOS.Plugin.Abstractions;
using LinkOS.Plugin;
 
 
namespace Printer
{
  public partial class PrinterPage : ContentPage
  {
  public PrinterPage()
  {
  InitializeComponent();
  }
 
  void Handle_Clicked(object sender, System.EventArgs e)
  {
Task.Run(async () =>
{
await Task.Delay(100);
var address = "AC:3F:A4:5B:1E:7E";
Print(address);
});
  }
 
IConnection connection;
 
private void Print(string address)
{
string zpl = "^XA^LL200^FO30,20^A0N,30,30^FDHello World^FS^XZ";
 
try
{
if ((connection == null) || (!connection.IsConnected))
{
connection = ConnectionBuilder.Current.Build("BT:" + address);
connection.Open();
}
 
}
catch (Exception e)
{
//if the device is unable to connect, an exception is thrown
Debug.WriteLine(e.ToString());
}
}
  }
}
 
When the application compiles against a real device in debug mode the following errors are thrown:
 
"_CGImageGetWidth", referenced from:
  -[GraphicsUtilCpcl printImage:atX:atY:withWidth:withHeight:andIsInsideFormat:error:] in libZSDK_API.a(GraphicsUtilCpcl.o)
  -[GraphicsUtilCpcl storeImage:withImage:withWidth:andWithHeight:error:] in libZSDK_API.a(GraphicsUtilCpcl.o)
  -[GraphicsUtilZpl printImage:atX:atY:withWidth:withHeight:andIsInsideFormat:error:] in libZSDK_API.a(GraphicsUtilZpl.o)
  -[GraphicsUtilZpl storeImage:withImage:withWidth:andWithHeight:error:] in libZSDK_API.a(GraphicsUtilZpl.o)
  "_OBJC_CLASS_$_EAAccessoryManager", referenced from:
  objc-class-ref in libZSDK_API.a(MfiBtPrinterConnection.o)
  "_OBJC_CLASS_$_EASession", referenced from:
  objc-class-ref in libZSDK_API.a(Zebra_EADSessionController.o)
  ld: symbol(s) not found for architecture arm64
  clang : error : linker command failed with exit code 1 (use -v to see invocation)
  
  MTOUCH : error MT5216: Native linking failed for '/Users/wesleyriley/Projects/InventoryManager/InventoryManager/InventoryManager.iOS/obj/iPhone/Debug/device-builds/ipad6.7-10.0.1/mtouch-cache/arm64/libzsdk_iosx.dll.dylib'. Please file a bug report at http://bugzilla.xamarin.com
Done building target "_CompileToNative" in project "InventoryManager.iOS.csproj" -- FAILED.
 
Done building project "InventoryManager.iOS.csproj" -- FAILED.
 
Build FAILED.
...
...
...
clang : error : linker command failed with exit code 1 (use -v to see invocation)
MTOUCH : error MT5216: Native linking failed for '/Users/wesleyriley/Projects/InventoryManager/InventoryManager/InventoryManager.iOS/obj/iPhone/Debug/device-builds/ipad6.7-10.0.1/mtouch-cache/arm64/libzsdk_iosx.dll.dylib'. Please file a bug report at http://bugzilla.xamarin.com
 
Note this error does not happen when running on a simulator. Unfortunately, I need a real device to test Bluetooth Zebra printing..
 
I am running the latest version of Xamarin and the latest version of Visual Studio. I have tried this in Visual Studio 2017 for Windows and VS 2017 for MAC with the same result.
 
Any help would be greatly appreciated.