It's not certain what tipped the balance for Xiaomi, although big phones like the Mi Note (shown above) likely helped. That leadership might not survive for much longer, however. As IDC warned earlier, the days of a rapidly expanding Chinese phone market appear to be over. Vendors are mostly trying to poach customers from each other, rather than enticing first-timers who are finally well-off enough to buy a smartphone. In a volatile climate like that, it might only take one hit phone (or a spectacular flop) to shake things up.

[Image credit: AP Photo/Jeff Chiu]