Yammer

If you want the functionality of Twitter but the privacy of a business network, the Yammer service offers a bit of both. You can use Yammer to send small, private, threaded status updates to members of a company that share an email domain. At the time of writing, Yammer clients for Android are rather underwhelming; instead, I recommend you access the service at www.yammer.com directly through your browser for a better user experience.