Develop OTT cross platform SmartTV application

We have an OTT online platform that is being built currently. We are building the web services needed to provide data to the SmartTV app via REST and in JSON. The app should be able to show available videos in the library to the user, make purchases, check the user's library of bought items, and other information related to videos uploaded. Design will also be provided to the developer. So the only thing needed is building the structure of the app and connecting it to the web services. The app has to be compatible with the major SmartTV providers like Samsung, LG, Sony (Opera), Philips, etc.