Add Rating System to Published Android App...NOW!

We need to add a rating system a published Android application. Our App: [login to view URL] Our app has a listview...seen here: [login to view URL] Our app sends and receives data to/from a MySQL database. Currently users can submit comments only. ****We want to enable users to submit "star" ratings with their comments and display average rating in the listview. #1) Enable user to submit "star" rating with comments (comments forms already working) #2) Add average rating to listview and seen in examples: [login to view URL] [login to view URL] #3) Add a sort button to our list view menu for "Sort by Ratings". PLEASE REVIEW EXAMPLE URL's BEFORE BIDDING. Only Bid if your ready to start immediately.