App that syncronizes files from a ftp folder to the local memory card.and then play this (like on atual website)

I have a website for a client to create multimedia content (posters) to play on a TV (normally on horizontal position -take care of this screen resolution when do the app-) in a bar/restaurant. For example, you upload an image of an offer, or a short video. You set the time (seconds) you want it to play, and it plays it. The issue is that the streaming is not going very well because is not a powerful server and customers haven’t stable connections. We need that the content be downloaded to the storage memory card of device and then, play the downloaded content instead internet content. Then, no matters If there is a little internet cut. The app must to check the ftp folder if changed content and download the new content every 5 minutes, for example, to synchronize) As summary, the app only must to play the content, like website, but from local storage to be fluid. App need to launched automatically (auto-start) and auto-login When play content we need don’t see any control bar, same like when you plays form website. On website [login to view URL] we have a backend with list of all users. We need to put: • A field to show if user is online or not • A button to restart the device of user? My budget is 120 USD. I will pay you if all requirements all done, because if not, client don't need the app.