Social video sharing apps are growing increasingly popular these days, users spent more time viewing and sharing content on mobile phones or tablets in detriment of video sharing platforms like YouTube and Vimeo (according to research firm Flurry).
Considering the recent Facebook buyout of Instagram, the competition between these 7 video social sharing apps is fierce, each one hoping to be the new ‘Instagram’ for videos.
1. Viddy
Viddy is a simple way for anyone to capture, beautify, and share amazing videos with the world. Capture key moments of your life, instantly produce it into a beautiful video, and share it with those who matter most. Videos are currently limited to :15 seconds.
Compatible with iPhone, iPod touch, and iPad.Requires iOS 4.3 or later

2. Socialcam Video Camera
With over 10 million downloads, Socialcam is the easiest way to capture, share and view videos on your iPhone. Now with vintage video filters, custom titles, and soundtracks!
Compatible with iPhone, iPod touch, and iPad.Requires iOS 4.3 or later

3. Klip Video Sharing
Create beautiful klips by applying effects to your videos. Capture and store videos of unlimited length on your device and enjoy unlimited uploads for free. Share videos on Klip, on Facebook, on Twitter, via email, via SMS or syndicate your video to YouTube.
Compatible with iPhone, iPod touch, and iPad.Requires iOS 4.2 or later

4. Keek
Keek is a revolutionary new way to discover the world and interact with others! Create & watch short video updates with your smartphone, tablet or laptop and share them with friends. Simple to use, extremely fast and 100% free. Join the social video revolution!
Compatible with iPhone, iPod touch, and iPad.Requires iOS 4.1 or later

5. Vyclone
Now when you shoot video with your iPhone you can include footage taken by your friends filming the same events. Just point your phones at something and record, Vyclone does the rest. In a few moments it synchronizes and edits everyone’s clips to create one movie with all the angles cut together.
Compatible with iPhone, iPod touch, and iPad. Requires iOS 5.0 or later

6. Tout Video
Tout allows users to shoot and share video status updates via smartphones, tablets and webcams. Capture moments from day-to-day life with the simplicity of taking photos, but better, with full motion and sound. Tout It Out!
Compatible with iPhone 3GS, iPhone 4, iPhone 4S, iPod touch, iPad. Requires iOS 5.0 or later

7. Looplr Social Video
Get in the Loop ! LoopLR is a fun, social real time video sharing app that lets you make cool videos on your device and share them on LoopLR, FaceBook and Twitter , make friends and bring them into your Loop, chat, hang out.



You missed the newest: Broadcast For Friends by Ustream.
http://broadcastforfriends.com/
Thank you for your suggestion Gergely!