Watchly Our pick
Best overall for Mac — free Prime co-watch, native, and cross-platform
Watchly is a native Mac App Store download built specifically for watching together in perfect sync. You start a room, pick Prime Video, and everyone's playback locks to the same second — press pause and it pauses for the whole group. Best of all, Prime Video is completely free to co-watch in Watchly; you do not need Watchly Pro for it.
Because Watchly also has native iPhone, iPad and Android apps plus a Chrome extension, the host can be on a Mac while friends join from a phone or laptop and stay in sync. Built-in push-to-talk voice chat, live reactions and text chat come included, so you don't need a separate Discord call running in the background — and unlike Prime's native feature, it isn't region-locked.
Pros
- Prime Video co-watch is free — no Pro subscription required
- Native Mac app with true Mac-to-phone cross-platform sync
- Built-in voice chat, live reactions and text chat
- Works everywhere — not limited by region like Prime's own feature
Cons
- Some premium services (HBO Max, Disney+) need Watchly Pro
- Each viewer still needs their own Amazon Prime membership