Twitter released revamped versions of its applications for Apple (NASDAQ:AAPL) iOS and Google (NASDAQ:GOOG) Android, optimizing the latter for devices running the new Android 4.0 Ice Cream Sandwich operating system, as well as Amazon.com's Kindle Fire tablet and Barnes & Noble's rival Nook Tablet.

The upgraded Twitter apps bring back the swipe shortcut feature, which enables users to swipe a tweet in their home timeline to reply to, retweet, favorite or share it, or view the Twitter user's profile, all without leaving the timeline. The app also adds a confirmation alert when consumers select "Find Friends," which enables them to more quickly identify friends on Twitter by uploading contacts' email addresses and phone numbers.

The refreshed Twitter for iPhone additionally brings back copy and paste for texts of tweets and user profiles, as well as expanded sharing within tweets, direct messages and greater control over font size settings.

Twitter now boasts more than 100 million active users worldwide, 55 percent of whom are active on mobile devices. According to the Pew Internet Center, 13 percent of adult Americans who go online are on Twitter.

For more:
- read this Twitter Blog entry

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