Andriod APP needs building

Hi We need a fairly simple App created, would be pleased if you can help subject to cost. What we require is an App that will have a menu such as Starters/Mains/Training/Procedures and listed in the menu will be under Mains for example food dishes by name and number reference and with photos of each dish, when an item it selected a recorded message will play giving instructions on how to prepare the dish complete with real time timings, ie “now put xxx in the wok, now keep moving around the wok until you are told to stop”, would be good that as the recording plays there will be silent gaps and it would be good that when there are these silent gaps that the user could listen to music that they have been able to load up and then when the silent gap ends and the recorded message starts again the music stops so the person can listen to the message without hearing the music. Would also want to be able to allow the user to view a video as an alternative to the recorded message. Will need an easy way to upload the recorded messages photos and videos as there will be a lot of them. We will want this to operate on Android tablets, maybe android phones. This App is ONLY for internal use by our staff. What you think can you help, have we given you enough information, if not please ask questions of us. Regards Ian.