The play button on the Bluetooth Media Button does not answer phone calls on iPhone. On Android devices, pressing the play button does answer incoming calls.

If you use an iPhone and want to answer calls hands-free, you have two options.

Turn on Auto-Answer Calls:

1. Go to Settings, then Accessibility, then Touch, then Call Audio Routing.
2. Tap Auto-Answer Calls and turn it on.
3. Set how long the iPhone waits before it answers a call automatically.

Use Hey Siri:

1. Go to Settings, then Siri and Search, and make sure Listen for Hey Siri is on.
2. Open Announce Calls and choose when calls are announced, for example Always, Headphones and CarPlay, or Headphones Only.

When a call comes in, Siri announces the caller, and you can say Answer or Decline. You can also say Hey Siri, answer the phone on speaker to answer hands-free.