The best way I think is to use the mobile hotspot like you mentioned. Regarding controlling via your android phone you could use a webpage with action buttons or build an app.
Webpage would be quick and easy. There are some good examples on how to control your device thru a webpage in this forum. I have personally modified the example in this post, placed those files in my SD card and used it to control my devices.
If you want to develop an android app, I would recommend MIT App Inventor or Tasker unless you are an expert app developer already. Tasker is my fav.