Common facade for the Azure Mobile Services end-point we've defined. Kept abstract to allow for platform-specific client APIs for Azure Mobile Services.

ServiceClient.cs

using System;
using System.Collections.Generic;
using System.Threading.Tasks;

namespace NinjaLocator.Core
{
    public abstract class ServiceClient<TAuthenticationProvider>
    {
        public TAuthenticationProvider AuhenticationProvider { get; set; }
        public string AuthenticationToken { get; set; }

        protected abstract void Initialize(string serviceUrl, string applicationKey);
        protected abstract Task LoginAsync(string authenticationToken);
        protected abstract Task LoginAsync(TAuthenticationProvider auhenticatonProvider);
        protected abstract IMobileServiceTable<T> GetTable<T>(); 

        public void LocateNinjas(Ninja requestor, Action<IEnumerable<Ninja>> ninjasLocated)
        {
            Initialize(Configuration.ServiceUrl, Configuration.ApplicationKey);

            Task loginTask;
            if (!String.IsNullOrEmpty(AuthenticationToken))
                loginTask = LoginAsync(AuthenticationToken);
            else
                loginTask = LoginAsync(AuhenticationProvider);

            loginTask.ContinueWith(delegate
                {
                    var ninjaTable = GetTable<Ninja>();
                    ninjaTable.InsertAsync(requestor)
                              .ContinueWith(insertTask => ninjaTable.ReadAsync())
                              .ContinueWith(readTask => ninjasLocated(readTask.Result.Result));
                }, TaskContinuationOptions.OnlyOnRanToCompletion);
        }
    }
}