Android App for Tablets

We need to develop an app for Android Tablets that are able to store 500 MB Files (Video and PDF) locally on the tablet. These Files should be able to be accessed after the download without a internet connection on the tablet. Also it should check on each start of the app on a server for new files and it has to be able that the user can check for new files and download new files fron the server to the tablet with a wifi connection. The app has not to be published on the apple store. We need the apk file to send to the users to install the app locally. Please apply only if you have min. 5 Years experience with android apps, if you can show us your android apps and if you speak english and german. All other applies will be ignored.