Apple's Siri: Cheat Sheet

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

...basic than Siri - requiring voice commands to be spoken precisely to be recognised by the system, and offering only limited functionality to connect calls or play music. Siri is much more capable - hence the need for additional service plug-ins.

In the US, Apple has agreements with third-party local maps and search providers to support a local look-up service. For instance, tell Siri 'I need a haircut' and it could pull up a list of barbers in your immediate vicinity. However, Apple does not yet have a deal with a local data provider in the UK - so no local look-ups for Siri users on this side of the pond.

On the capabilities front, Apple says Siri's got artificial intelligence smarts - claiming it will get better over time as it becomes accustomed to your voice and the kind of things you're looking for. Apple also says Siri is "proactive" - meaning it will question its owner until it knows what you're looking for and can act accordingly, rather than giving up at the first incomprehensible word.

The result, reckons Apple, is a more naturalistic dialogue. "Ask Siri to do things just by talking the way you talk", the Apple website says, adding: "Talk to Siri as you would to a person." This NLP-plus-AI approach makes Siri different from Apple's earlier mechanical voice controls - which basically just involved a human repeating pre-set commands at a microphone.

But aren't there other voice assistant apps out there? Doesn't Google's Android already do something similar?
There are indeed other NLP apps. There are other voice assistant apps too such as Vlingo, which offers apps with similar functionality to Siri for various smartphone platforms including iOS. Vlingo also lets users connect to some third-party apps, as well as native phone apps, so users can speak a tweet or tell their phone what to update their Facebook status to - something not currently supported by Siri. Vlingo also allows users to open apps by voice command - another Siri no-no.

Google has also been investing in voice tech for a while and its Search app allows users to speak search queries instead of typing them. Google Translate also lets users speak words and phrases they want translated. Meanwhile, Samsung's Galaxy S II Android-powered smartphone comes loaded with a Siri-esque virtual assistant - in the form of the Voice Talk app, powered by Vlingo.

Apple is by no means the first to the punch when it comes to NLP, but it is making a big push on the voice front by integrating Siri into its latest iPhone. Expect voice smarts to be a key component of all future iPhones.

Alright, so Siri looks pretty cool but speech recognition tech has been around forever - why the big fuss? Is it just because Apple's got involved?
Certainly, Apple getting involved does signify a certain level of maturity has been reached. NLP tech is a lot better...