Website development

I require a website that allows users to post pictures and text behind a letter in a wall of letters, to be known as the "wall". site home page is just a grid of the letters of the alphabet (as shown in attached) A4 etc etc, by clicking on the each letter it opens a small view window where the user-owner can post a picture and some text, the idea is the user-owner posts updates to each letter so behind each letter box is some news/info that relates to that letter i.e. A4Apple, B4bike, i.e. C4 click on C4, open a window title C4car (user can edit the title extension word, in this case "car") and the user could post a picture of the new car with some words i.e."my new sports car" - its meant as a quick update/news/social/gossip info for the user on the user, the idea being that behind each letter is something relating to that letter, D4 could show a photo of my new dog etc etc etc. The user can then invite friends to view their wall. Each user registers and creates an account, normal user account and password functionality required - other registered users can then see the walls of other users, but not edit the info. Need functionality for signed in users to search for other users, "Search Walls" box bottom right. They can however leave posts - short text messages - in the "Posts" box at the bottom right, which all users can also see. Within the Home box the user can post a picture of themselves and a quick short text message. Needs to be nice and simple design and blocky graphics letters with photo upload. Mobile app functionality to follow.