Startup Pointy Heads Software hopes to making "knocking" synonymous with live content-sharing on mobile phones. The Danbury, CT.-based company has released a new iPhone application that promises to let users share photos with other iPhone owners instantly without having to go through the usual uploading and downloading process via the Web.

The company refers to its direct mobile-to-mobile file-sharing technology as "knocking" and plans to launch a series of apps based on the software it likens to screen-sharing tools used online for presentations or video conferencing. "We're not storing any large amounts of data, so where someone using AT&T is struggling to send five pictures via email we can send up to 100," said Jim Montalto, co-founder of Pointy Heads, launched in March.

After setting up an account and creating a photo album through the company's Knocking Live Pic Sharing app, a user sends an alert through the Apple push notification service that results in a message and a knocking sound (instead of a ring) on the iPhone of a friend who also has the app installed. The photo-sharing session begins when the other person responds.

In addition to sending up to 100 pictures at a time, the app lets the recipient browse the photos at their own pace while the friend who sent them looks on -- simulating sitting together to flip through a print photo album. (A live chat feature is planned for future versions.) People who receive photos can also send ones they want to their own devices.

So far, the Live Pic Sharing app has earned a rating of three and a half out of five stars in the iTunes App Store, based on ratings from 32 users. The 11 reviews were mostly positive, although some suggested the user interface could be improved. "The concept of the app is great and it's A LOT faster than MMS (multimedia messaging service) but the user interface is so confusing that many new users will be turned off," began one review.

While photo-sharing app at launch can only be used among iPhone users, Pointy Heads plans to make it available on Android, Symbian and BlackBerry phones starting early next year, as well as enabling use across different handsets. To help spread adoption, the company is offering the first 50,000 downloads free, but will begin charging $1.99 for each after that.

Pointy Heads also intends to roll out "knocking" apps for sharing other types of content including streaming video. "The knocking suite will expand to other things you might want to share from your phone to others," said Montalto, who declined to elaborate beyond a forthcoming video-sharing app.