One new thing was custom silicon for local, cloud-free audio processing, https://www.slashgear.com/amazon-skips-the-cloud-with-local-.... When combined with US-firmware Zigbee on Echo 4, it allows local device control by voice, without any internet connection. But now they are sadly dropping that to send all audio to the cloud for LLMs.
The failed Alexa software ecosystem was such a lost opportunity, as the device even ran Android. Their hardware ecosystem was more successful, e.g. voice-controlled microwave sold many units with happy customers who still complain about discontinuation of the affordable device. They experimented with niche devices, e.g. make or answer calls on an existing landline, using any Alexa device. Also sadly deprecated, for much weaker VOIP limited to 10 correspondents and random outbound caller ID.
The failed Alexa software ecosystem was such a lost opportunity, as the device even ran Android. Their hardware ecosystem was more successful, e.g. voice-controlled microwave sold many units with happy customers who still complain about discontinuation of the affordable device. They experimented with niche devices, e.g. make or answer calls on an existing landline, using any Alexa device. Also sadly deprecated, for much weaker VOIP limited to 10 correspondents and random outbound caller ID.