Close on the heels of its last-week announcement that it was dropping its `invite-only' requirement and allowing the masses to sign up for accounts, social-bookmarking service Pinterest has now released new apps for the Apple iPad and Android-based devices.

The availability of new iPad and Android apps marks a notable expansion for the 2011-launched Pinterest - a visual bookmarking tool that helps users collect and organize content which they find online by theme - which has thus far been available only on the Web and via its popular app for the iPhone.

The iPad Pinterest app boasts some wonderful new user interface touches which have been brought on to give the users a speedier experience than the regular Pinterest app. The app also has an embedded browser which takes the users to the brand sites of the products they double click on, and allows them to view the other same-brand products that users have pinned --- all within the app.

Noting that the iPad app offers a much better pinning experience than the app's regular version, with the most significant difference being the in-app browser, Pinterest co-founder Evan Sharp said: "It's a really different kind of browsing experience."

Meanwhile, the free Android Pinterest app - which is now available in the Google Play store and will likely hit the Android Appstore soon for Kindle Fire users - has been built by Pinterest engineers from `ground up', and has been optimized to work on a wide array of Android-based smartphones and tablets.