A photography app that has become incredibly popular in recent weeks after adding an anime makeover feature has been sending user data back to its developer in China.

Meitu carries out checks to establish if an iOS device is jailbroken and collects information about its carrier before passing it onto Xiamen Meitu Technology. It’s thought the company could be selling the information to marketing agencies for targeted ads.

Mainland China is Apple’s second biggest market, and will one day be its first. The company is making a big push on the mainland, opening new stores and investing in home-grown companies. Why the interest? Because China is the new Japan — it’s where the future is happening. All this week we take a look at the cutting-edge apps that define mobile life on the mainland.

SHANGHAI CITY, China — Just like their U.S. counterparts, Chinese youth obsess over their smartphones. But while the phones they use look the same, the apps are quite different: China has its own must-have apps that keep users’ eyes glued to screens at all hours of the day.

Some Chinese apps seem quite similar to their Western counterparts, but others boast innovative and intriguing features. Apple’s clearly interested: While slowing growth in China put a dent in APPL stock, Cupertino recently made a strategic $1 billion investment in Chinese Uber rival Didi Chuxing.

What other apps in China might grab Apple’s attention? Tim Cook could start his due diligence with this list of powerhouse Chinese iPhone apps. The country’s young people use these apps to listen to music, make purchases, get around town, interact with others and maintain their online identities.

These Chinese apps are impressive and convenient, and they are showing us the future of mobile: a world where everything is at our fingertips.