“A cellular operator may collect data from you, supposedly to improve how you set up your phone for the first time,” said Bryce Boland, Asia Pacific chief technology officer at FireEye, an internet security firm.

"It's not that it's specific to any handset maker or telco."

"It's more of an industry problem, where organizations are taking steps to collect data they can use for a variety of purposes, which may be legitimate, but potentially also have some privacy concerns," he added.

However it's not just the carriers collecting data, even the handset maker’s grabbed data from your phone. But what kind of data, when, and for what is not revealed.

"If we look at the content sent by many apps, it's mind boggling how much is actually sent," said Boland. "It's impossible for someone to really know whether something is good or bad unless they know the context."

“Handset makers need to be clear with users about what they're doing and why,” said Carl Pei, director at OnePlus, a Shenzhen, China-based upstart rival to Xiaomi. “OnePlus collects ‘anonymous statistical information,’ such as where a phone is activated, the model, and the version of software that runs on it,” Pei said, “which helps them make better decisions about servicing customers and where to focus production.”

Unlike Xiaomi, Pei said, OnePlus' servers are based in the United States, “which in the light of recent privacy concerns,” he said, "gives people greater peace of mind than having them based out of China."

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