Write a multiplatform Xamarin mobile app for iOS, Android and Windows Phone 8.1

A software consultant (agencies and businesses prefered) is needed to build a multi-platform app covering iOS, Android and Windows 8.1 and must be written in with Xamarin, utilising Xamarin Forms where relevant and MVVMCross. The initial phase will contain the following functionality: * Secure and safe user self registration and login mechanism, accounting for high volume usage This is critical and needs to be very secure and handle a high volume of users Ability for users to change passwords and request password reset * Azure based database and WCF services (I will provide the cloud hosting) * Approx 10 distinct pages/forms to be built * WCF service to retrieve app data from the database * Ability to choose an image from the photo library or photo capture functionality using the device's default photo capture software (not custom code) * In app Advertising capability * Conversion of images and data into PDF documents at server side * Extraction of data and images from database and convert to excel export These are the list of major technologies that must be used: * Xamarin * XAML * MVVM * WCF * Windows Azure Mobile Services (Optional) Please note there are some services that will be provide by us in order to support the build process: * All graphics * All Windows Azure services * SQL Server configuration and database build * Exchange server for email * Any external web pages required to support the app * TFS Online Potential Phase 2: A responsive website (for desktop and tablets) that provides the same functionality as the app with the addition of bulk administration. User would be able to upload and download bulk information. Potential Phase 3: Additional pages and detail on each existing page plus a secure and private messaging system between linked app users. Digital signature capability (using signature pad/hand/stylus). A Potential Phase 4 also exists. Full functional specifications are available and will be forwarded to suitable bidders. The contract will be fixed price, but we will require you to break down the costing by functional component as described by the design document. This is to ensure that bidders read the requirements and we are considering realistic solutions and prices. Please remember to request the full requirements specifications for your bid. In order to be considered, please provide a summary of the following: * Your experience and skills * Portfolio of previous work done with Xamarin (we will need proof that you know Xamarin well) * Any public facing multi-platform apps you have written in the past * Sample source code showing what quality of coding you can provide NOTE: We will also require you to provide a solution breakdown of the requirements once you have received it. Please request a copy with your expression of interest. Please do not bid without a proposal or a detailed explanation of your ability to complete the job successfully. If you have any questions, please contact me to discuss.