The battery life is more than 600 measurements, or approximately 2 years if used once every day.
To get the most battery life out of your QuickCare, keep your phone nearby when taking new readings.
If your phone is not nearby, QuickCare will keep transmitting readings to your phone over that greater distance until it succeeds, which uses up more energy.
The Kinsa app can receive readings from your QuickCare in the background. You don't have to open the Kinsa app for it to receive readings from your Kinsa thermometer.
The QuickCare uses one replaceable CR 2032 battery. They're available at all pharmacies, most grocery stores, and online at Amazon.com, Target.com and Walmart.com. They're usually sold in packs of five, for around $5 per pack.
If you have a choice of brands, we recommend Panasonic or Energizer - whichever you find cheaper.