Twitter's mobile video service Vine has been enhanced with the addition of new features designed to make it easier to shoot with the app and to share videos. Twitter's engineers have redesigned the camera and included new grid, focus, and ghost tools to make shooting videos easier.

The app also introduces 15 channels for users to submit posts to or browse from the Explore screen, including comedy, music and nature - each with their own theme and Popular feed.

The update also includes a setting called protected posts that will reduce the amount of sharing on the service. Most Vine posts today are public, but people can now turn this setting on so that only people who users approve can see their posts.

The "On The Rise" feature also allows Vine users to discover new people who are starting to capture the attention and interest of the Vine community.



Users are also able to share other people?s posts with all of their followers in one tap.

These new features are available now on iOS. Protected posts will also be available in an Android update later today, and the other features are coming to Android next week.

Twitter launched Vine in January, as a way for people to share quick videos.

Yahoo is also trying to become competitive in mobile video. On Tuesday announced its acquisition of Qwiki, an app that makes short movies out of people's previously shot photos and videos.