Li Yifeng.

The brand started using him for public occasions when he returned to China from South Korea, where he was a member of the former K-pop group Exo.

When Wu went to Switzerland for the watch and jewelry show Baselworld this year, his activities were streamed live on the internet, allowing fans using smartphones to keep up with what he was doing. It was estimated that more than 50 million viewers watched live.

Wu is also the face for the British luxury brand Burberry in China and walked down the runway for the brand as a star guest during London Fashion Week last year.

Still, some collaborations can be too bold for luxury consumers.

The Swiss watch brand Jaeger‑-LeCoultre chose to work with Papi Jiang, a video blogger who built her name on self-made comedy skits, on a video campaign aimed at young people.

At the center of the campaign, drawn up by the advertising firm Fred & Farid, was the Reverso model, one of the brand's more affordable models.

In the video, restricted to the brand's WeChat account, Jiang, wearing a Reverso watch, talked about her rise to fame and what she thought about it.

No sooner had the campaign begun than tongues began wagging, with many questioning the compatibility between a Swiss watch and an internet personality who had made her name through dry wit that often crosses into sarcasm.