Question about Netatmo Smarter smoke detector set of 3

The smoke detector does not require a subscription (all Netatmo products work without a subscription), but a free Netatmo account can be set up to receive smartphone notifications and to connect the smoke detector to Wi-Fi. However, the smoke detector will also work on its own without any Wi-Fi installation, in which case it is simply not 'Smart', meaning that no notifications will be sent to your mobile devices.