Samsung’s problems with the exploding Galaxy Note 7 handed back smartphone leadership to the iPhone, but far bigger problems overshadowed a strong set of quarterly results from Apple, including significant loss of share in China, and continuing declines in tablet sales. According to figures from IDC, three local handset makers – Oppo, Huawei and Vivo – now account for almost half (48%) of unit sales in China, while Apple’s shipments in the world’s largest market fell during Q4 after a period of recovery. Apple was in fourth place in the market last year, says IDC, with Xiaomi in fifth. The Chinese challengers are launching increasingly sophisticated models at better prices than Apple, and so the iPhone 7 “did not create…