Here's a step-by-step guide on how you can go about recording Slo-mo videos in 1080p resolution on your iPhone 6s or iPhone 6s Plus.
How To Enable iPhone 5s Slo-Mo On iPhone 5, 5c, 4s And Other Unsupported Devices In Stock Camera App
When Apple announced the iPhone 5s last September, one of the features that it made quite a fuss about was the new phone's ability to record slow motion video.