Create A Cross Platform App for IOS/Android/Window for Blog Website

Hi, we are Looking for Individual/Team Expert in Making Cross Platform Mobile App for our Blog website for All three Platform Android/IOS/Windows. Job Function => It Fetches Blog Contents Written on Our Website AND Backend, Also Need to Configure Background such that it makes Easy for App to fetch and Synchronise all the Contents and Updates. Need to be careful for it not to Crash. Must be Compatible for all Mobiles in these Platforms. Provided Input => We'd Provide all the details, Complete User Interface Design in PSD, and other things needed to start Development. Thanks