The Apple watch was 100% post-Steve, conception to delivery [0]. This is definitely the first post-Jony Ive product though. (Rumors are that Ive was against the idea of doing a headset from the start, so it happened either without him, or after he left, depending on when it started.)
- [0] https://www.wired.com/2015/04/the-apple-watch/
> Ive began dreaming about an Apple watch just after CEO Steve Jobs’ death in October 2011.