OTTAWA — There are plenty of signs suggesting that John S. Chen, chief executive of BlackBerry, should sprint as fast as possible away from making phones.

Handsets drove the company’s initial success, but they then brought it to the edge of financial ruin, an also-ran behind Apple and Samsung. Even Mr. Chen, who was brought in last November to salvage BlackBerry, has made it clear that the company’s future lies mainly in selling mobile data management security and services to governments and corporations.

But on Wednesday, BlackBerry reached for smartphone magic once more, introducing the Passport, the first major BlackBerry device since Mr. Chen’s arrival. If the phone fails, it will most likely signal the end of BlackBerry’s handset business instead of its revival.

The company presented the phones on Wednesday at big events in London, Dubai and Toronto. Yet in an interview this month, Mr. Chen suggested that BlackBerry had comparatively modest goals for the Passport, which features a novel square display and a physical keyboard that doubles as a touch-sensitive track pad.