Apple's Siri: Cheat Sheet

The iPhone 4S' virtual voice assistant - ask and you shall receive (an answer)...

Siri? Isn't that Tom Cruise and Katie Holmes' firstborn?
No, no, you're thinking of Suri. I'm talking about Siri. Or rather, I'm talking to Siri. And Siri is talking to me.

Siri sounds talkative.
Indeed, that's because Siri is a voice assistant application that comes with Apple's latest iPhone - the iPhone 4S.

Apple iPhone 4S: Siri Cheat Sheet

Siri making itself useful on the iPhone 4SPhoto: Apple

What's a voice assistant?
It's a piece of software that responds to verbal commands. Siri is a natural language processing (NLP) app that can recognise and respond to speech. It responds both verbally, via synthesised speech, and where appropriate by pulling up and displaying relevant data on the user's iPhone.

Examples of actions Siri can perform include taking dictation, sending emails and text messages, scheduling appointments and reminders, locating information, playing media and making phone calls. Apple says Siri uses almost all the built-in apps on the iPhone 4S - plus data from the web - to "find the information you need".

Siri's technology is reportedly powered by US company Nuance, another speech-based interface tech company, under a licensing agreement with Apple. It's worth noting that Siri is a beta app at present and currently supports only three languages: English, French and German.

But what powers Siri?
As well as NLP tech, servers on the back end and the phone's hardware itself, Siri makes use of Apple apps such as its weather app and a local search data service from Yelp in the US to summon the answers its users seek. Siri also reportedly utilises the Wolfram Alpha search engine to help it respond intelligently to factual queries.

Wolfram Alpha utilises organised data and a variety of algorithms and equations to generate relevant answers to text-based queries. Ask it what the GDP of France is, for instance, and it will return that figure, along with a variety of associated data such as the recent history of France's GDP perhaps plotted as a graph. Siri similarly aims to be so smart - but more mouthy.

I don't have an iPhone 4S - can I get Siri on my iPhone 4 or 3GS?
Not from Apple itself, although various people have been trying to hack Siri onto other iOS devices. But via official channels, the app is iPhone 4S-specific for now.

Can I tell Siri to fire up my psychedelic disco flashlight app without me having to get out of the lotus position then?
Not at present. Siri only works with native iPhone apps such as the iPhone alarm clock app or calendar. It doesn't work with third-party apps because Apple hasn't opened Siri up to its developer massive. If it did that, the possibilities for talking to your phone really would be - ahem - massive.

How long has Apple been cooking Siri up then?
Well, we know that last April Apple acquired Siri Inc, a company that had launched an eponymous voice-activated personal assistant iPhone app - which Apple subsequently removed from the App Store as it worked to bake Siri into the 4S. So the iPhone 4S's vocal sidekick has been in the pipeline since at least 2010.

Apple has had a more basic voice control feature in iOS devices since iOS 3.0, however. iPhone 3G S, iPhone 4 and iPod Touch owners can access this feature by holding down the home button to activate the system and then telling their device to 'call Jony Mobile' or 'play artist The Beatles'. The system can also respond to being asked 'what time is it?'.

This voice control feature is much more...