All of the MQTT apps are user written. There are at least 3 (linked below). Each have their own threads for support/instructions. There is no easy button - just need to read up in those threads. Each app has its own pluses and minuses depending on your wants/needs.
In my opinion, based on your description the last one in the list may fit your needs to best (?). The first one in the list has the most support and user base though.
