Add Private Messaging, Commenting and Social Sharing on an Android App

I have an Android app that needs added features. It is a listings app similar to ebay but local for a city only. App is working and connected to an online database. Currently registered users can leave a feedback and rating to another user, so I believe the code can be recycled and used for Commenting and Direct Messaging Here is what I need to be added: Comment Section In Listing Details Page - display 3 newest comment under "Recent Comments" - must have a "View All" button - must have a "Leave A Comment" button (only available when user is logged in) - display pop-up dialog for commenting when comment button is tapped - pop-up dialog will contain a Message input field and "Cancel" and "Submit" buttons - when View All button is tapped, display comments in a new screen, as user scroll down it should load comments one by one not all at once (like Google Play Store) - so comments on a listing are stored in DB and only gets deleted when seller deletes listing - comments must have a date displayed - popup dialogs when submit comment success and resend dialog when submit comment failed Private Messaging - Display as "Send Private Message" button in user profile when other user want to PM - When "Send Private Message" button is tapped display pop-up dialog with input fields for "Subject" and "Message", with buttons "Cancel" and "Submit" - Display as "Private Messages" button when profile owner want to view and respond to private messages. - When "Private Messages" button is tapped display screen showing lists of messages with user avatar, username, PM Subject, receive date and delete icon - When delete icon is tapped, remove PM from list and also delete the PM in DB - When a private message is selected display private message screen - this screen will contain senders avatar, username, receive date, subject, message, Delete and Reply buttons - needs pop-up dialogs when sending success and resend dialog when failed Social Share - users must be able to share a listing in social networks etc. - the title, description and image must be fetched and is put on the social network the user want to share in (not the link because viewers will not be able to view it, just a simple share with tile, description and image) Wireframes are provided for better explanation. Source code and DB/cPanel access will also be provided. Developer will have a chance to work for more features. Please try the demo APK to better understand how app works.