Tech Tent: Silicon Valley strikes back

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The week began with Silicon Valley bosses coming out of their shells and speaking out against President Trump's immigration policy.

But by the end they were turning their minds to other matters - some spectacular results from Facebook and Apple and the prospect of the biggest stock market debut by a tech firm for years.

On my Tech Tent podcast this week, we discuss the hopes and fears of Silicon Valley as Snapchat owner Snap gets ready to hit the New York Stock Exchange.

We also hear from a London tech chief on his worries about the US migration policy. And you'll be pleased to hear there's a gadget on the show as we find out how augmented reality may enter the classroom.

Putting the Snap back in Silicon Valley

When a company that lost more than $500m (£400m) last year announces it is floating on the New York Stock Exchange with a $25bn (£20bn) valuation, there are two possible reactions.

Either Snap's initial public offering (IPO), at a time when its growth is slowing, is a sign that the market for tech firms has gone mad again with investors betting on a future that will never materialise, or it just reflects renewed confidence in Silicon Valley at the end of a week where both Apple and Facebook have confounded the sceptics with record-breaking revenues.

Snap chief executive Evan Spiegel

Remember, Facebook's $100bn (£80bn) IPO valuation was derided by many in 2012, but today it's worth nearly four times as much. Snap will hope to follow the same path rather than that of Twitter, which is now worth less now than when it floated.

Snap shares are bound to take investors on a rollercoaster ride - so we try to work out where they will end up.

Migrants and Money

When President Trump's executive order banning travel to the US from seven predominantly Muslim countries was published, one tech company boss had a very personal take.

Ismail Ahmed is the founder of WorldRemit, a London-based business helping migrants send money home.

Ismail Ahmed runs WorldRemit

He is a British citizen but was born in Somalia, one of the countries on the banned list. (Actually he hails from the peaceful self-declared independent state of Somaliland - but that's not a distinction likely to be obvious to border officials).

He tells us he was pretty worried when the news of the ban broke. After all, he has to travel frequently to Denver where his US operation is based. He already has problems at the border because his name is similar to that of the spiritual leader of the militant group Hamas. Despite the fact that Sheik Ahmed Ismail was killed by Israel in 2004, his name is still on a sanctions list - hence Mr Ahmed's problems.

He is now somewhat reassured about his future travel plans by the intervention of the British government on behalf of its citizens. But he says that with 330 staff and 35 nationalities on the WorldRemit workforce, any restrictions on their ability to travel will be a concern.

Then there are his customers, current and future: "There are 250 million people who live outside their home countries who then send an estimated $600bn (£480bn)."

His message is that migration is not going to go away: "Ever since homo sapiens left east Africa 50,000 years ago, we've been on the move... Brexit or no Brexit, Trump or no Trump, people will continue to travel."

AR in the classroom

Over the last three decades, all sorts of technological innovations have entered the classroom in schools around the globe. First came PCs, then electronic interactive whiteboards and notebook computers and in recent years some schools have decided that giving every pupil a tablet is the way forward.

Could the next big trend be the use of augmented reality, where digital information is superimposed over the real world?

At the recent Bett education technology fair in London, Jane Wakefield tried out Hololens, Microsoft's augmented reality headset - or "mixed reality", as the company prefers. It offers a new interactive way to teach children a range of subjects. They can, for instance, walk around a skeleton to learn how it fits together.

We discuss whether this is the future of education - or just a fad.