PhotoTag is a mobile application that uses HTML5 and geolocation to allow users to tag photos with location data and view nearby photos taken by other users. The app was originally developed using PhoneGap to package a HTML5/JavaScript website into a mobile application for cross-platform deployment. However, the initial version experienced issues with inconsistent geolocation and camera performance on some phones. As a result, the developers have moved to creating a native mobile application instead of relying on HTML5, pending further standardization and cross-browser support of HTML5 capabilities on mobile platforms.