How does cold weather in Hokkaido affect my phone and eSIM?

Extreme cold doesn’t damage your eSIM profile itself, but it can significantly affect your phone’s battery and behavior. At temperatures below about –10°C, lithium-ion batteries drain much faster and phones may shut down even when they still have charge. To reduce problems, keep your phone in an inner pocket close to your body, use a small power bank as backup, and limit how long you expose the device to the cold when taking photos or checking maps. Also download offline maps in case low temperatures or remote locations temporarily affect your ability to use mobile data.