Smule has just launched a new video app - Strum - that turns your short video clips into music video masterpieces. The Strum app for iOS looks to join the likes of Viddy, Socialcam, and Klip as the 'Instagram' of video, adding one-click filters to clips recorded on your iPhone.

The one key difference between this app and others like it on the market is that it allows users to play with the audio as well.

At first glance, it has a navigation similar to the photo-sharing app, Instagram, with a bottom row of five icons allowing users to navigate to a feed of videos from people they follow, browse popular videos, take and share a video, follow friends' activity and visit the profile page.

The app allows users to shoot videos as long as 15 seconds and share them on the Strum network as well as post them to Twitter, Facebook and YouTube.

"Video is infinitely more expressive than photos." Smule's general manager Prerna Gupta told Mashable. "One of the things that makes video more powerful is the audio content. Video makes audio better, the opposite is also true." 

"We always wanted to do something with video," Smule's chief scientist, Parag Chordia, told Macworld. "There's really not any product out there that allows you to simply create videos that look and sound good, and that really enhance what you've done in an intelligent and automatic way."

The app comes with 21 filters that alter audio and video in tandem. The "Ecstacy," filter, for example, autotunes a user's voice and plays dance tracks to make them sound like a pop singer, while the "Spacer" filter autotunes the voice so that users sound like they're rapping, with on-rhythm clapping in the background.

Strum enters a crowded market for video filtering apps, dominated by Viddy which already boasts 40 million registered users, but even that pales in comparison to the standard-bearer in this area, Instagram, which has more than 100 million users.

However, Smule is no stranger to the world of smartphone apps, having combined more than 75 million installations of its music app offerings which include Ocarina and Magic Piano.

Strum is available to download for free for iOS 6 devices, such as the iPhone 5. The company plans to introduce new filters which can be downloaded within the app for a premium.