Coming off an earnings release, shares of BlackBerry (BB -1.92%) seem to be showing signs of life. The company reported a 10% boost in its gross profit margin by selling 6 million BlackBerry devices, which 1 million were of the BlackBerry 10 variety. However, aggregate subscriber growth still remains an issue for the company. In this video, Motley Fool contributor Steve Heller discusses the report and what he'd like to see before calling shares a long-term buy.