Get Android's SIM ICC Id and device's IMEI number

DroidTelephonySimInfo.cs

// Requires the following permission in your AndroidManifest.xml
// <uses-permission android:name="android.permission.READ_PHONE_STATE" />

using System.Collections.Generic;
using Android.Telephony;
// ...
protected override void OnCreate(Bundle bundle)
{
  base.OnCreate(bundle);
  
  SubscriptionManager sm = Android.Telephony.SubscriptionManager.From(Android.App.Application.Context);
  IList<SubscriptionInfo> sis = sm.ActiveSubscriptionInfoList;
  SubscriptionInfo si = sis[0];

  string carrier = si.CarrierName;
  string iccId = si.IccId;
  string phoneNum = si.Number;

  System.Diagnostics.Debug.WriteLine("Carrier: " + carrier);
  System.Diagnostics.Debug.WriteLine("SIM Card IccId: " + iccId);
  System.Diagnostics.Debug.WriteLine("Phone Number: " + phoneNum);

  // Bonus, Get the Device Id (aka, IMEI Id)
  TelephonyManager tm = (TelephonyManager)GetSystemService(Android.Content.Context.TelephonyService);
  string deviceId = tm.DeviceId;

  System.Diagnostics.Debug.WriteLine("Device Id: " + deviceId);
}