Google on Friday said it had acquired Sparrow, the startup behind the well-regarded Sparrow email client for iOS and OS X, for an undisclosed amount.

Google already distributes a native iOS client for Gmail, its Web-based email service. The company says it intends to use Sparrow's engineers to contribute to the ongoing development of Gmail, but declined to provide specifics.

"The Sparrow team has always put their users first by focusing on building a seamlessly simple and intuitive interface for their email client," a company spokeswoman said in an email. "We look forward to bringing them aboard the Gmail team, where they’ll be working on new projects."

Since Larry Page became CEO last year, Google has put a greater emphasis on the appearance of its products and services--design and user interface--than it did previously.

[ For more on Google, read Google Revenue Robust, CEO Recovering. ]

On its iTunes Store listing, Sparrow says there will be no further updates to its email client, apart from maintenance and bug fixes.

The Sparrow deal, Google's fifth this year, comes with engineering talent that's sure to be useful to Google. Co-founder and CTO Hoa Dinh Viet used to work for Apple, on iCal and iSync, and for Amazon, on its Kindle e-reader.

Google may see an improved native email client as a way to compete more effectively with Apple Mail. Apple Mail, available on both iOS and OS X, can be used to access multiple email services, while the iOS Gmail client handles only Gmail. Turning Gmail for iOS into a service-agnostic email client, perhaps for OS X as well as iOS, could help Google convince Mail users to switch to its software.

Recent additions to Google's Chrome browser indicate that Google still sees Web apps coming up short when compared to native apps.

In addition, complaints about Gmail performance in Mail appear to be quite common. Whether this issue is related to competitive decisions or technical problems, Google has more of an incentive to address Gmail responsiveness than Apple.

Writing apps is expensive and complex. Cross-platform tools can help, but they're far from perfect. Also in the new, all-digital Develop Once, Run Everywhere? issue of InformationWeek: Why the cloud will become a more accepted development environment. (Free with registration.)