I live in Vietnam. Windows phone is certainly popular here, but I believe (relying on my own biased observations) that iPhone is vastly more popular. While iPhones are sold by official vendors, it's far more popular to buy "hand carry" phones that are imported by individuals. Of the ~10 people I know with iPhones, all are hand carried. They are cheaper than the official vendors (and not recognized in the IDC report).
Windows Phone in Vietnam are more of a cheaper phone (comparable to Android devices) rather than compete directly with the expensive iPhones. For those customers who can afford the iPhone, they will buy the iPhone instead of a high end Nokia Windows Phone.
Skunkworks.vn - A 30 person and rapidly expanding mobile app developer working on an unannounced project. Our Primary office is in Vietnam, but we are also hiring out of San Francisco. Please visit our site http://www.skunkworks.vn/careers/ or contact hr@skunkworks.vn
Engineering:
Senior iOS Developer,
Senior Mobile Web Developer,
Android Developer,
Automation Testing Engineer,
Technical Writer,
Database Analyst Engineer,
Linux Systems Administrator
Product Operations:
Customer Experience Lead,
Senior User Experience Designer
Not really. Ours is founded by an American who has lived here for 11 years and, having previously founded and sold companies in France and California. It's sort of an American company in Vietnam, more so than a Vietnamese startup :)