PopBooth turns your iPhone or iPad into a photo booth, prints and all

The folks over at mobile photo-printing startup Sincerely have been fast and furious in recent months. First came the company’s April debut with the launch of Postagram for iPhone (s AAPL). Then came last week’s update of Postagram for iPhone and launch of Postagram for Android (s goog). Next up is an entirely new product, PopBooth, set to launch by month’s end.

PopBooth allows you to take photo booth-style photos with an iPhone or iPad 2 and have physical copies of the photo strip sent to you through the mail.

The PopBooth process is pretty straightforward for anyone who has ever used a traditional photo booth: You stand in front of the iPhone or iPad’s self-facing camera, press the shutter button, and pose for a series of four concurrent photos. You then have the option to add one of several filters on the photos, such as black and white or jewel-toned overlays. PopBooth photo strips can be shared for free on Facebook and Twitter, and Sincerely will print and mail two copies of a PopBooth strip to you for a yet-to-be-determined price.

PopBooth will be available for one-off use or in “party mode,” which will allow a user to purchase a package of a certain number of prints. I could definitely see folks setting up an iPad at a wedding or party and using PopBooth strips as a fun gift for guests — a much less expensive alternative to the increasingly popular rented photo booth.

The Sincerely team’s hard work seems to be paying off: The company is set to move into a new 5000-plus square-foot office space in downtown San Francisco — digs I’m told the venture-backed startup is paying for entirely with its own revenues. If PopBooth takes off as well as Postagram has, Sincerely’s recent success could be just the beginning.