In February 2013, China surpassed the United States to become the world’s largest smartphone market. More than half a decade on, it still proves an elusive target for international sellers. A glance at reports from the past several quarters reveals the top spots dominated by homegrown names: Huawei, Vivo, Oppo, Xiaomi.

Combined, the big four made up roughly 84% of the nearly 100 million smartphones shipped last quarter, per new numbers from Canalys. Even international giants like Apple and Samsung have trouble cracking double-digit market share. Of the two, Apple has generally done better, with around 6% of the market — around six times Samsung’s share.

But Apple’s struggles have been very visible nonetheless, as the company has invested a good deal of its own future success into the China market. At the beginning of the year, the company took the rare action of lowering its guidance for Q1, citing China as the primary driver.

“While we anticipated some challenges in key emerging markets, we did not foresee the magnitude of the economic deceleration, particularly in Greater China,” Tim Cook said in a letter to shareholders at the time. “In fact, most of our revenue shortfall to our guidance, and over 100 percent of our year-over-year worldwide revenue decline, occurred in Greater China across iPhone, Mac and iPad.”

When it came time to report, things were disappointing, as expected. The company’s revenue in the area dropped nearly $5 billion, year over year. On the tail of two rough quarters, things picked up a bit for Apple in the country. This week, Tim Cook noted “great improvement” in Greater China.