Ignore the hype over big tech. Its products are mostly useless | John Harris

It’s years since Silicon Valley gave us a game-changer. Instead, from curing disease to colonies on Mars, we’re fed overblown promisesBack in 1999, Google hit 1bn searches a year. Wifi began to make an impact about two years later. Thanks to the pioneers of Facebook and Twitter, the age of mass social media dawned between 2004 and 2006 – and non-stop posting, messaging and following was soon enabled by the iPhone, launched in 2007. These things have changed the world and, in hi