OTTAWA — BlackBerry, the hobbled smartphone maker, reported more dire financial news on Friday, posting a $4.4 billion loss and a 56 percent drop in revenue in its latest quarter. The company also outlined a sharp retreat from its once-core handset business by entering a partnership with the Asian contract manufacturer Foxconn.

The loss, which follows one of nearly $1 billion in the previous quarter, again reflected the failure of the BlackBerry 10 line of phones, which were portrayed as a lifesaver for the company when introduced at the beginning of the year. The latest loss included a $2.7 billion write-down mainly related to BlackBerry 10 phones, including the Q10 and the Z10.

Of the 4.3 million BlackBerrys bought by consumers and businesses during the quarter, 3.2 million were models that use the obsolete BlackBerry 7 operating system. The meager sales of the phone led revenue to plunge to $1.2 billion, compared with $2.7 billion in the same period a year ago.

Last month, BlackBerry failed to find a buyer for the company and replaced Thorsten Heins, the chief executive, with John S. Chen, the former chairman of the software company Sybase. Mr. Chen has since fired several high-level executives at the company.