Google has purchased Word Lens, an impressive app that translates foreign languages in real time using the iPhone and Android smartphone built-in camera. It's now free for a limited time.

Image credit: Apple

Back in 2010, a company called Quest Visual debuted a little app called Word Lens. It scarcely seemed possible, but the app translated a number of different languages in real time using just the smartphone's camera. When traveling in a foreign country, Word Lens users would simply hold the phone up to a sign and the camera would immediately translate it.

Currently, users can translate between English and Portuguese, German, Italian, French, Russian, and Spanish.

It's easy to see why Google would want to own it -- its stated mission is to make all the world's information searchable in any language -- and Google Translate generally does this quite well, at least for web pages.

With Word Lens, iPhone users can translate the world. Apple even featured the app in its recent "Powerful" television ad for the iPhone 5s, and it's obvious why.

Even better, it doesn't require a connection to the internet, which is another benefit for business travelers.

Word Lens isn't perfect. It has trouble with particularly stylized text or handwriting, and the translations will make occasional mistakes. However, most of the time, it will at least get the point across.

No financial terms on the acquisition, which was announced on Quest Visual's website, were disclosed. Neither company shared details on what the future holds for Word Lens either, other than the website saying that the app and language packs would be "free to download for a limited time," while the Quest Visual team transitions to Google. Individual language packs previously cost $3 each.

Image credit: Quest Visual

The app itself is free to download from the App Store for both the iPhone and iPad, and I couldn't recommend it more highly. The translations are available via an in-app purchase, though they are currently free. It's also available on the Google Play Store for Android users.

Because we don't know how long Word Lens will remain on the stores, I recommend that you pick it up as soon as possible, particularly if you travel internationally.

Word Lens is truly one of the killer apps for mobile, and it should be a staple on every phone. Here's hoping that Google keeps it around in some form or another and doesn't kill it off.

What about you? Do you have a situation where you used -- or should have used -- Word Lens? Let us know in the comments below.