Tech Tent: Alexa speaks louder

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We were promised jetpacks, we ended up with 140 characters. That's the cynical take on how Silicon Valley's dreams of life-changing innovations ended up producing something as mundane as Twitter.

Mind you, in the week that Twitter gave us 280 characters - a dubious advance - Tech Tent does indeed bring you the personal jetpack, or at least a competition to build one.

We also hear about Amazon's latest ambitions for its Alexa virtual assistant, and discuss the growth of ransomware as a major cyber-security threat with Europol.

Amazon wants people to use its Echo speakers everywhere

Amazon's Alexa ambitions

When Amazon launched its Echo voice-controlled speaker three years ago, it may at first have seemed just an interesting but minor sidebar to its main business.

But it quickly became clear that the Echo and the Alexa assistant at its heart was a big, bold statement about the company's ambitions. Amazon wants to use its artificial intelligence (AI) expertise to enter the home and develop an even closer relationship with customers.

This week the company stepped up that campaign and unveiled a whole series of new Alexa-based devices.

There is a revamped Echo, an Echo Plus, and an Echo Spot, a device with a screen. Stuart Miles of the tech blog Pocket Lint tells us he thinks there is a danger that consumers will be confused. "They may think, 'I'm not sure which one I need', and they will panic and walk away and buy something else."

That something else could be the Google Home connected speaker. This week saw shots fired in the battle between the search firm and Amazon. Google removed YouTube from the Echo Show - yet another screen-based device - complaining that it created a "broken user experience".

Amazon says it does not understand Google's complaint and users are losing a service they valued.

Just as Apple used to be close to Google and put features such as maps on the iPhone until the launch of rival Android phones, the battle over connected speakers is causing new tensions between the tech behemoths.

Amazon has 5,000 people working on its Alexa portfolio, and you can bet Google too has an army deployed on its mission to get us talking to its technology. This is a battle where both firms are determined to spend billions in pursuit of victory.

The UK's National Health Service was hit hard by the Wannacry ransomware

Cyber-crime - the growing threat

"It's growing so quickly that we've got to run to stand still" - that is the sobering assessment of the battle against cyber-crime from Steven Wilson head of Europol's cyber-crime centre.

It is ransomware which is identified as the biggest danger in the annual internet crime threat assessment produced by the European law enforcement agency.

Malicious software which locks up your data until you pay off the criminals is becoming a "multi-million, even billion dollar business," according to Mr Wilson.

Europol's report describes the evolution of what it calls cyber-crime as a service. "People without a technical capability can now purchase ransomware and deploy it."

The good news is that major attacks like the Wannacry outbreak have increased public awareness of the threat. The bad news is that 100 new varieties of ransomware have been spotted over the last year, and the threat against businesses and critical infrastructure continues to evolve.

Science fiction is full of jetpacks although they remain absent in real life

Flying dreams

If you wanted evidence that the tech world can still think big, just turn to Elon Musk.

The Tesla tycoon's Space X business has transformed the economics of the satellite industry by showing you can land and reuse rockets.

Now Musk says his new rocket the BFR - please don't ask what that stands for - will fly passengers around the world in 60 minutes and send astronauts to Mars as early as 2024.

But here's another example of blue sky thinking - a $2m competition to build that staple of sci-fi - a personal jetpack.

Sponsored by Boeing and run by a start-up called GoFly, the contest will encourage teams from around the world to come up with designs.

Entries must be capable of carrying a person 20 miles (32km) without refuelling or recharging, with a vertical or near vertical take-off and landing.

"This is about making people fly - this is the stuff of your childhood dreams," Gwen Lighter, the founder of GoFly, told us.

She says the arrival of new technologies like drones, better batteries and autonomous steering systems have made this idea technically feasible.

Cynics will say that nobody is going to want to strap a jet engine to their trousers and the idea of the skies abuzz with jetpacking commuters will not delight air traffic controllers.

But as a vision of our future isn't it more attractive than giving some Twitter trolls 280 characters to express themselves?