Mobile app and thermostat to not sync bi-directionally. It caused a failure in our furnace to not start one cold winter morning forcing a technician to come out. Not happy with this product at all. In addition, it is not Alexa enabled.
Very easy to program and easy to use. I have two of these at my beach house and can the AC or Heat on when my family is headed there for a visit ( 4 hour drive).... Love these devices.