Boxcar isn’t a full-featured Twitter client, but rather a client dedicated to providing Push notifications of all Direct Messages, Replies, and Mentions, as well as providing an application dedicated to sending and receiving direct messages. I’ve posted a full review of the application over at Obsessable, where we’re also giving away several copies of the application over the next week. Read that full review for all the details. I find the application useful, although I wonder how long it will be before some of the already popular Twitter clients add this functionality and thereby render Boxcar obsolete.
Review rating: YAY! (if Boxcar works with your current Twitter client of choice)
It’s important to note that all Twitter push notification systems right now are really being faked, as the Twitter API doesn’t support Push. To work, people are having to poll your Twitter account on regular intervals to fake Push notifications.