Xiaomi has resumed growth and global revenue should surpass $15 billion this year as an expensive gamble on India pays off, billionaire co-founder Lei Jun said. Bloomberg reports that after spending $500 million in the subcontinent since its debut two years ago, he pledged another investment of that size over the next three to five years. Xiaomi has had a challenging few years but its business is once again expanding at a healthy clip, Lei said in an interview. He expects to double revenue in India this year to $2 billion. Beyond hardware, the company chalked up $1 billion of revenue in 2016 via the 10 million-plus active users of its suite of mobile apps and services, he added. Lei is betting India holds the key to rejuvenating Xiaomi, a brand that once ruled the roost in China but has since been eclipsed by local rivals.