What's the difference between an instant-read and a wireless smart meat thermometer?

An instant-read thermometer (like the Thermapen ONE or Alpha Grillers) gives you a fast spot reading when you stick it in, then you pull it out. A wireless smart thermometer (like ThermoMaven, Typhur Sync Gold, CHEF iQ Sense, or MEATER) has a leave-in probe that streams internal and often ambient temperatures to a base or phone app over Bluetooth/WiFi, which is far more useful for long smokes and brisket where you don't want to open the lid.