Choosing a Technology Stack for Your Mobile App Backend

You need a backend for your mobile app.
Do you use a BaaS like Firebase or roll your own custom backend?
If you’re rolling your own backend, what database to use? MySQL or MongoDB?
What about server hosting? EC2 or DigitalOcean?
I made the Backend Decision Making Matrix to help with some of these decisions.
Here’s the download link to the PDF:
Backend Decision Making Matrix
Feedback or suggestions appreciated!