IPhone
A minor upgrade to the iPhone 4 was the iPhone 4S. It came on October 14, 2011, and had a new feature called Siri, which is a voice activation system. Additionally, it is able to record videos in 1080p resolution, which is 2.25× times higher than 720p, so that each still frame from the video contains more details. This makes it possible to see smaller items on the footage in a sharper, clearer way. Additionally, it allows zooming into the video to see more details.