BlackBerry's market share has been on a long steady decline in recent years, with consumers increasingly turning to Android and Apple devices instead.
But in a slip-up for the mobile phone manufacturer, it turns out even its own social media team is using an iPhone instead of one of its own handsets.
A post from BlackBerry's official Twitter account showed a "Twitter for iPhone" stamp on it. Although it wasn't visible from the site itself, it was visible on other platforms like Tweetdeck and Tweetbot.
After being spotted by the eagle-eyed Norm Kelly, a Toronto city councillor, and picked up by The Verge, a presumably red-faced BlackBerry employee has since deleted the tweet.