For now, with this small number of participating retailers, this isn't necessarily the most useful feature yet. If Google actually manages to get more businesses to use this feature (and/or to expose their inventory through an API), then Google Product Search - which has remained relatively underused - could easily establish itself as the go-to local shopping service.

For more details about the mobile version of Google Product Search, have a look at this video (the introduction of Product Search starts about 19 minutes into the presentation)

Another bonus: if you're not actually in a store doing some shopping, you can use the app as a custom interface to Google's Product Search portal. With the provided search box, you can either type in a product name or just speak into the phone's microphone and Google Shopper will retrieve results - much like how Google's standalone mobile application does with web searches.

Why Does Google Need Another Mobile App?

If you own an Android mobile phone, then you've probably already installed one or more mobile shopping companion applications. ShopSavvy, for example, was one of the first barcode scanners on the scene. Designed mainly to scan high-end goods like DVDs, CDs, books, and consumer electronics, after scanning a barcode, you're provided with a list of both local and online prices for that same item.

Amazon, on the other hand, wanted to go beyond the barcode. With its Amazon App for Android, you can scan barcodes but you can also snap a photo of an item using the phone's camera. Amazon then searches through their inventory for that item and displays either the item itself or a similar product if the catalog doesn't have that exact item available.

Then, of course, there's Google Search for mobile and the related downloadable application. From either web interface, the Shopping vertical is easily accessible - only a tap away under the "More" section. So what prompted Google to release a dedicated shopping app like Google Shopper? Perhaps they saw the success of Amazon and ShopSavvy and wanted to redirect mobile users back to their engine and their search results?

While that's obviously a major factor in the decision, it's notable that Google Shopper is only available at launch time as an Android application. If there was ever any doubt that Google plans to favor their own mobile platform over rivals from Apple, Windows Mobile, RIM and others, we can put that to rest now. Whether Google is or is not working on a version of the app for other mobile platforms is almost besides the point. If they are, then how clever of them to launch the Android version first instead of waiting until everyone could use it, and if they aren't...well, then specialized Google apps for Android just became a huge selling point for the phone, didn't it? If we had to guess, it's the former - after all, as much as Google wants to promote their mobile OS, they're more interested in search traffic and multi-platform mobile applications are the way to get more of that.

For Android owners, Google Shopper is available now. You can grab your copy from here.

I'm not a big shopper but I have struggled while standing in stores to find product reviews on my phone for tennis racquets, vacuum cleaners and power tools within recent memory. Natural search results and Amazon listings only worked so well. Unfortunately, a lot of shopping searches I tried this morning didn't have Product Search results. When they are available, they are pretty good though.

The best thing about the new inclusion of Google Product Search may be its availability in Google Voice search as well. That's handy, or hands-free as the case may be.

Google Product Search is the new name, as of two years ago, for what used to be called Froogle. That product never gained much traction, but speaking as a likely user of this new feature - I hope it continues to improve.