Philips Hue bulbs, for example, can be added directly from the Google Home or Apple Home apps.
Big smart-home brands offer easy compatibility with the major ecosystems. Philips Hue bulbs, for example, can be added directly from the Google Home or Apple Home apps. Unfortunately, this isn't common. Most devices will require you to use a third-party app for the initial setup at the very least, and possibly also for configuration and control.