Oops! BlackBerry sends out tweet from an iPhone

When tweeting, try not to do it from a competitor's device.

That's the lesson BlackBerry learned Tuesday after the Canadian device maker was caught sending out a tweet from an iPhone on its official account. The tweet featured a photo of a BlackBerry device and encouraged its followers to "keep up with the conversation" by downloading Twitter for BlackBerry.

The embarrassing tweet was quickly deleted but not before The Verge snapped a screengrab of it. The tweet could not be seen from Twitter's main app but was visible on TweetDeck and Tweetbot.

A spokesman for BlackBerry refused to comment on the tweet.

Once the device of choice for executives, BlackBerry has seen its fortunes wane in the face of competition from iPhone and other smart phone makers.

The company responded to mounting losses by appointing CEO John Chen and unveiling a new BlackBerry Classic. It seems to have worked - sort of. The company reported that it lost $148 million, or 28 cents per share in the third quarter. That compares with a loss of $4.4 billion, or $8.37 per share, a year earlier.