Home audio hardware design

I need a simple audio hardware design/schematic to manage 8 zones of already wired left/right speakers in my home and two out by the pool. I think I would like a page on my iPad and iPhone which gives me all options of what music I wish to stream, (only one stream for all 8 zones at a time). Off/on for each zone, and volume. Do I simply need an app, a good amplifier, solid wifi connection, smart speaker selector…?
No problem if this isn’t the type work you do.
Thanks just the same,
Steve