Vark is a free app that provides answers to those nagging questions.

Ever been engaged in a ragging trivia battle with a bunch of your buddies but could not agree on any of the answers provided by anyone and wished that you have some sort of a referee at hand to provide the final answers? Well, like the ads said, there is an app for that, and it is called Vark available at Vark.com.
According to the New York Times, Vark is available free for the iPhone and works this way: You will need to go register at Vark.com and list your areas of expertise and your Facebook page because it will use your social network as well your friends' networks to assemble the widest circle possible. But still quoting the New Y0rk Times, it will work without a link to Facebook by sending your question to selected volunteers, experts in the field of your question. If you have signed up using your Facebook page, when you ask a question , only a handful of people in your network or your friends network would be asked to provide an answer
which usually arrives within five minutes via instant-message, e-mail or through the iPhone itself.

For more, see NYTimes.com

TwitVid, a free app for tweeting videos.

Smartphone owners wanting to use their mobile device to post a video to go with their tweets, now have options in the form of apps.
For instance, Blackberry users now can post short videos on Twitter from their phones using an app called TwitVid which is one of several such apps that are available on the iTunes App Store for a while.
According to the New York Times, TwitVid is easy to use. After downloading the free app, users will look for the "record" function then record their video, enter their tweet and hit send. From there, the tweet will appear as usual on users' Twitter page with a link to the video which stays st0red in TwitVid servers with no limit on the length.
Anyone with a camera phone can use the service without downloading the app by simply visiting the company Web site at TwitVid.com . Once there, users will be assigned to be used to send videos as an MMS or an e-mail with the video as an attachment with the tweet in the subject line. After that, it will post just like a normal tweet.