I've been using my Honeywell wifi thermostats since 2013 with no issues. You can use a mobile app, a web portal, or link with an assistant like Google or Alexa. At least until the past couple of years. In the past couple of years there has been several outages that occurred with their cloud service that made the thermostat unusable through their online portal/ & app for either part of a day or longer. Probably less than 5 days altogether in the past 7 years or so that I took notice of. The manual controls still functioned like normal.