Vine for iOS is a new social networking app that revolves around making short 6-second video loops with sound and then sharing them with others.
To get started, you can sign up with an e-mail and password directly with Vine or you can use your Twitter account for quick access. Once signed in, you'll see the Home feed that shows the latest videos from other users. A button in the upper-left corner lets you navigate between the home screen, a place to explore videos from other users, a personal activity section to view videos you've made, and a link to your profile. I recommend going to the profile screen right away to fill out your information and also to use the button in the upper right to search for other Vine users you know from your address book, Twitter, Facebook, or a direct search. With a few friends selected, the home screen will now show videos from your friends and other contacts.
The home feed is the place to view the latest videos from people you follow, and as you swipe to scroll, you'll see you can do familiar actions letting you "like" a video and make comments. What's really neat about the home feed is that as you scroll, each video starts playing automatically while you have it on screen, while scrolling to the next video automatically stops the previous one and starts the new one. This automatic setup makes for a seamless experience as you scroll through and look at user-made videos.
The Explore page is a great way to see how other people are using Vine. There are links at the top for editor's picks, videos that are popular right now, and a link to all posts. But the app also has a grid of common hash tags, if you want to drill down to specific topics.