Full Test Results: iPhone 6s and 6s Plus

With the lab coats on hangers, the instruments powered down, and the spreadsheets filled out, here's the verdict from our tests of Apple's new phones: The iPhone 6s and 6s Plus are easily among the best smartphones available today.

The Peek and Pop feature of the 3D Touch interface can save you time by letting you preview appointments, e-mail contents, and other app elements without committing to opening the apps themselves. That feature also lets you perform other app operations without abandoning the app you're currently using.

The camera is great, too. The phones' 12.2-megapixel camera is among the best we've seen for taking still images—beating the 8-megapixel one in the iPhone 6 and 6 Plus.

That's the good news. Unfortunately, battery life is noticeably shorter for both models. In our talk-time tests, for instance, the 6s Plus lasted just 13.5 hours, while the 6 Plus kept the conversation going for an impressive 17 hours. The gap was smaller for the 6s: 8.5 hours of talk time compared with 10 hours for the older model. (Talk time is just one of several tests we do to evaluate battery life.)

Camera Details

Our image-capture testing is meticulous, and it confirms that the iPhone 6s and 6s Plus record textures, patterns, and shadings in greater detail than the older iPhone 6 models do, although you'll really need to zoom in on your photos to tell the difference. We found noise in low light and color accuracy to be comparable to what we've seen with iPhone 6 models.

Video performance, however, was a little worse because of color inaccuracies. Subjects appeared slightly pinker under indoor lighting conditions and a little more yellow in outdoor light. Like the original iPhone 6 and 6 Plus, the new phones had a tough time focusing while shooting video under low-light conditions.

These are the first iPhones that can shoot 4K video, and we saw a level of clarity you just don’t experience with an HD camera. (Of course, you’ll need an ultra high-definition TV to see your 4K content on a sizable screen.)

We also looked at Live Photo, which records 1.5 seconds of video before and after you snap a still photo, adding a dose of animation to the image. Live Photo looked cool, but it didn’t really add a lot of value. And there was a price to pay for Live Photo—storage space. We shot a number of test images and found that the files needed for Live Photo were three times as large as the still photo files alone. (That ratio may vary with the subject and lighting conditions.)

Finally, we looked at the 5-megapixel front-facing camera, which offers selfie takers two new advantages. The camera’s wider-angle lens allows you to squeeze more people and background scenery into your shots. And the phone’s display acts as a flash by lighting up briefly when you snap the shutter. This helped the camera take better shots under low-light conditions.

For full performance results on the iPhone 6s, 6s Plus, and many other smartphones, check our smartphone Ratings.