BBC Click's Nick Kwek looks at some of the week's best technology stories including:

The co-founder and chairman of Alibaba, Jack Ma, steps down from the e-commerce giant

The world’s longest road trip in an electric car was completed in a journey from China to Germany

A colour-changing ink, which reacts to different wavelengths of light, is developed by Massachusetts Institute of Technology

See more at Click's website and @BBCClick