Here are the latest steps for uploading a video you took with your iPhone camera directly to your Snapchat story.
Note: The old method of selecting a video and sharing it to the Snapchat app no longer works.
Note: Using Snapchat memories is the same as sharing the photo or video previously from camera roll. The only difference is Snapchat will show a white border around the photo/video if you share it this way in the Snapchat app.
Note: If your video is longer than 10 seconds, the Snapchat app will split the video into multiple video snaps.
You will notice a white border around your story when you or someone else views it. This basically means the photo or video was not originally taken with the Snapchat app (but, it could have been, if you saved it originally to your camera roll then re-uploaded it).