As one of its daily deals, B&H Photo Video offers the TP-Link Smart WiFi Light Switch 2-Pack for $39.99 with free shipping. That's $5 under our October mention and and the best per-unit price we've seen. (It's also $20 under the lowest price we could find for this quantity elsewhere.) It's compatible with Android and iOS devices via the free Kasa app and works with Amazon Alexa for voice control of fixtures and any WiFi router. Deal ends today.