Though many Sonos users may not realise it, you didn't always control your Sonos system with an app on a phone or tablet. When Sonos launched back in 2005, it did so with the CR100 controller, a now rather chunky remote control that did the job.
But 13 years is a long time in wireless audio and Sonos has now told customers that the device is no longer fit for purpose. From "early April", it will no longer be supported, and an update will mean it no longer connects to Sonos systems.
In an email to customers, Sonos said the CR100 can no longer "support many of the services and functions that are core to the Sonos experience". Furthermore, the old lithium ion battery inside has "the potential to overheat when left charging".
Sonos has suggested users use the free Sonos app on a phone or tablet instead, while offering them a £100/$100 voucher towards a future Sonos purchase. And while some Sonos owners are unhappy, it doesn't seem too bad a deal to us.
Sonos has supported legacy hardware better than many companies recently, and 13 years seems a fair lifespan for a device that is ultimately replaceable for free.
And if you really want to keep using it, you could ignore any future Sonos updates and take the risk with that liable-to-get-hot battery. But we wouldn't recommend that...