Shareholders of BlackBerry are being asked to remain patient ahead of the smartphone maker’s latest plan  to once again become profitable.

Chief executive Thorsten Heins  has told the company’s annual meeting that it will take time, and he could not predict  when due to the volatile smartphone industry.

Heins says the firm expects to return to profitability in the final stage of its three-stage plan, and admits investors have made it clear they want better results and faster progress.