Peng Liyuan was spotted taking pictures with a Chinese smartphone during a State visit to Germany last week with her husband, President Xi Jinping. A year ago, the gadget in Peng's hand was an iPhone 5.

The first lady's "change of appetite" has put inexpensive, made-in-China smartphones with special features under a spotlight.

Peng's Nubia Z5 Mini, from Shenzhen, Guangdong-based ZTE Corp, was powered by a 13-megapixel camera that can do such things as capture panoramic images.