PALO ALTO, California -- Apple CEO Tim Cook described China as "the most competitive market in the world" as the tech company reported lackluster quarterly results Thursday due to weak demand in the world's second-largest economy and stiff competition from Huawei Technologies.

Apple revenue declined 4.3% on the year to $90.75 billion for the three months ended March 30. iPhone sales dropped 10.5% to $46 billion.