Blackberry Limited has released its fourth quarter and full year results, posting a net profit in Q4 of $28 million on turnover of $660 million, which compares with a net loss in the final quarter of last year of $423 million on turnover of $976 million. For the year, Blackberry narrowed its net loss to $304 million from $5.8 billion a year earlier, while turnover halved to $3.3 billion from $6.8 billion.