Comment and Private Messaging Feature

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 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 delete PM and all the conversations in PM from 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 when failed 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.