I recently retired my old S4 Apple Watch, and planned on giving it to a family member. She has an iPhone 8 plus running iOS 16.7.15, the newest version her phone supports.
Apple's Apple Watch Series 4 Technical Specs Page says that you only need an iPhone 6 with iOS 12 to use the S4. However, when I tried to set the watch up with her phone, the Watch app said that it was incompatible.
I have an iPhone 12 Pro Max and had updated the watch to the newest version of WatchOS it supports, 10.6.2. What Apple never mentions on any of their tech support pages is that WatchOS 10 requires at least iOS 17, which her phone cannot run.
So, by updating the OS on
