While the HomePod and the Apple Watch require an iPhone even for the initial setup, the AirPods do work with Android phones but with many limitations, such as no wear detection or multi-point ...
While there is (still) no dedicated Apple TV app for Android phones and tablets ... you can easily watch TV+ content with it as well. However, there’s no current support for Android mobile ...
WIthout it, the Apple Watch is more like a paperweight, so that's something to consider if you have an Android phone. If you do have an iPhone, however, the Apple Watch will feel like an extension ...