Home smart devices in general. I'm avoiding Alexa, Siri or any other thing like that. Besides the obvious privacy issues I see about them, I can only imagine being alone at home, Alexa thinking something talked to her and responding in a distorted voice. No, thanks.
I'm considering a home assistant at some point, by setting up a proper network for the smart devices alone, but that's as far as I'll go.
Look for devices that support Zigbee or Z-wave, as they're guaranteed to be local-only and not depend on any cloud service. Pair them with Home Assistant and you'll have a smart home that doesn't require anything in "the cloud".