The Kelvin K2 uses the latest Bluetooth technology (Bluetooth 4.0), which is connected to the newest air technology to send temperature information to your smartphone. The free iOS and Android app then monitors your wine as it cools and relays the information to you, allowing you to get the best out of every bottle of wine. Every wine expert will tell you that wine flavor is composed of a combination of numerous key elements, each of which is drastically (and uniquely) affected by temperature. Therefore, each wine has its own optimal serving temperature.