There's no need to use a hub to connect the intelligent smoke detector to the Internet. The detector connects directly to a 2.4 GHz Wi-Fi network via the Hombli application.
No, the siren of the Hombli Smart Smoke Detector cannot be completely deactivated, so only an app notification is issued. The siren is an integral part of the device and sounds loudly (over 85 dB) when smoke is detected. However, you can mute false alarms with the Hombli app, but the siren will always sound initially before you can mute it.
Yes, the smoke detector has a WLAN module and connects to the app via WLAN.
The battery cannot be replaced, life span according to Hombli is 10 years. After 10 years, the other components are no longer in perfect condition, so the battery cannot be replaced.
No plan is required.