Blockchain could track cannabis sales and other news

BBC Click's Jen Copestake looks at some of the week's top technology stories including:

  • Blockchain technology that could provide a secure way to track the legal sale of cannabis in Canada

  • Self-balancing electric roller skates developed by Segway-Ninebot are to be banned on UK public pavements and roads

  • Waymo has announced a trial where self-driving cars will ferry shoppers to and from a nearby Walmart store to pick up their groceries

See more at Click's website and @BBCClick.