Apple’s Siri and True Knowledge’s Evi could be sisters. Both are voice-controlled virtual assistants that happen to respond to questions with exactly the same voice. They look similar, and they’re both intent on accommodating your every command. And yet, according to William Tunstall-Pedoe, founder of True Knowledge, Siri had nothing to do with his company’s impetus for creating Evi.

“The impetus wasn’t to create a competitor to Siri,” Tunstall-Pedoe says. “Evi is actually just the natural progression from what True Knowledge has been doing for the last four to five years.”

So what has True Knowledge been doing for the last half a decade? In short, the company has been trying to create a better search experience.

“We’d already built the platform that could answer direct questions without keywords,” Tunstall-Pedoe says. “And then about a year ago, we decided that we were going to launch our own branded product rather than creating a platform that we license out to others.”

Conversational search was the object behind Evi. “Voice is the most natural way to search for information and voice recognition has improved in a relatively short period of time to the point where it’s actually the most efficient way to search on a mobile,” he says.

Regardless of whether it was the intent or not, Tunstall-Pedoe acknowledges that Siri is a competitor, but he says the underlying technology is completely different. “The heart of Evi is millions of facts creating a machine representation of what the user’s asking, inference, etcetera, while Siri works very differently,” he says, adding that the platform upon which Evi sits has more similarities with Wolfram Alpha than with the core Siri technology.

That “core technology” is nothing to dismiss. Tunstall-Pedoe explains that Siri’s categorizes what the user says into a vertical and does a transaction in that vertical, typically by calling an external service (Yelp, Yahoo, etc.). Evi, on the other hand, creates a semantic representation of what the user says and if it is a question. She will answer it from knowledge already known to the platform.

“In reality, Evi has expanded beyond the core technology and now integrates a variety of sources and other techniques into the platform as well,” Tunstall-Pedoe says, but Siri has also expanded. However, the core question answering capability is still there.

To put it plainly, Evi was designed to answer simple, factual questions from its always increasing knowledge base. For instance, “What is 83kg in lbs?” or  “How many feet are there in a yard?”

“Evi will understand and answer these kinds of questions directly, it’s a core capability,” Tunstall-Pedoe says. “Siri will not understand, call out to Wolfram Alpha and then display its response.”

True Knowledge doesn’t have plans to white label Evi, but it does hope to open up the API to developers, so that they can access the cloud-based platform. Tunstall-Pedoe says that the more devices and applications that interact with Evi, the smarter she’ll become.

Evi launched on Jan. 19 and is available for 99 cents on the Apple App Store. The cost of the app goes to cover the Nuance speech-recognition licensing. A free beta version of Evi is also available from Android devices on the Android Market. 

So Who Should You Hire?
I asked a set of questions to both Siri and Evi, with mixed results from both. Both of these services should improve as more people use them, but in their current forms they’re sort of hit or miss. However, because their improvement really is dependent upon human input, Apple’s Siri sort of has the upper hand here, as she’s guaranteed a spot on every iPhone 4S and higher sold from here on out. You can draw your own conclusions from the results below.

What is the height of the White House?

Evi: I found this on the web: “almost as tall as the tales of hope its male occupant spins…”
Siri: data not available (queried Wolfram Alpha)

What is the square root of 432?

Evi: 20.7846096908
Siri: 20.7846096908

How many miles in the Autobahn?

Evi: Suggested I ask Cha Cha
Siri: Suggested I search the Web. Found the answer at Wikipedia: 7,965 

Where’s the nearest sushi restaurant?
Evi: Suggested I ask Cha Cha
Siri: Provided 8 restaurants within 5 miles of my current location.