China has shown time and again the power it can wield over American technology companies. Facebook is blocked in the country, as is Twitter. Microsoft and Qualcomm have faced investigations by Chinese authorities. Numerous other companies have tried to crack the vast market and failed.

Now add another tool that China is using that demonstrates its clout over foreign tech companies: technology reviews.

Chinese officials have quietly begun conducting reviews of tech products sold in China by companies such as Apple, write Paul Mozur and Jane Perlez. The reviews, which require company executives or employees to appear in person, involve consumer software and mainstream devices and looking at the products’ encryption or data storage.

The reviews have been undisclosed and unconfirmed until now, write Mr. Mozur and Ms. Perlez. The meetings are set to raise questions about the amount of information that foreign tech companies must give up to do business in China, and what — if anything — is done with the information obtained during the reviews.