Android application with instant feed from online DB

The main task is to create android application that will run on Lifeview ([login to view URL]). This device will be connected to TV which will be displaying application. Application would need to have 4-7 blocks on UI. It means that picture on screen of the TV needs to be split to blocks. In every block would be one of the media elements (picture, video, moving text). Basically it would be info screen with some new information and pictures of the company. This application needs a connection to internet to leach information from database. Device will be connected to DSL cable internet. Database will contain text and URLs of pictures and videos for TV advertisement application. The key function is that this application needs to download new data from database every 15 - 30 minutes and determine if there's new data. Something like synchronization with database, but it needs to download to local memory all new objects (pictures, video text) and delete those which are not there anymore. It's because we need to be independent of internet connection, in case that connection is lost. In that case application continues to show old info and it will try to download data for 15 min again. Hope it's clear enough in case you have further questions feel free to contact us. If you have any ideas how this could be simpler please suggest them. Regarding to budget we're open for your suggestions. Thanks for taking interest for our project.