When you first launch the app, you'll see your home feed, which displays all the recent videos from the people you follow. Below each post, you can add a comment, like the video, or revine it (repost it to your account).
In the Explore tab, you can see some of the top videos created in Vine. The app organizes videos into Channels, so you can browse through videos by specific category, like Comedy, Cats, or Food. There are links at the top for the most popular videos and those that are gaining attention.
From any tab in the app, you simply touch the camera button at the bottom of the screen to get to the camera. Then touch anywhere on the screen to start recording. The icons at the bottom give you advanced recording options, such as tapping to focus on a subject and displaying a grid to keep your video level.