A slimmer phone means scaling back on some components, including the battery. The Galaxy S25 Edge has a 3,900 mAh battery, compared to 4,000 mAh on the baseline S25 and 4,900 mAh on the S25 Plus. Samsung says the S25 Edge's battery should last you all day, and in my experience so far, this has been true -- but don't expect any more than that.

We should also note that if you're excited for the year of thin phones, you'll have to wait for the rumored iPhone 17 Air to get an ultra-slim Apple smartphone. Samsung Galaxy S25

With its ultra thin construction, Samsung's only able to cram a 3,900 mAh battery inside of the Galaxy S25 Edge. We put it to the test to see how long it lasts.