Google is upgrading mapping services to woo users and swipe back at Apple, which is nudging aside the location tools on its own mobile devices.

Apple plans to unveil a mapping application next week that will come pre-installed on its iPhones and iPad tablets, replacing Google Maps.

Google, whose mapping app has been on the iPhone since its unveiling in 2007, today announced a feature that gives users access to maps even when they're offline.

The feature initially is only available on devices using Google's Android software.

"I'm very proud of Google Maps services and they're available basically on all devices today," Brian McClendon, vice president of engineering for Google Maps, said at an event today in San Francisco.

"We'll continue to make Google Maps services as widely available as possible." Google and Apple have increasingly clashed as the two companies compete for users of mobile devices and related services, such as music and movies.

Google's Android operating system has emerged as the most widely used smartphone software, and will command 61 per cent of the market this year, while Apple's iOS will rank second, with 20.5 per cent this year, according to IDC.

With the new mapping option, users can select a portion of a map when the device is online that can later be used when the device is no longer connected to the Web, Rita Chen, product manager for Google Maps for Mobile, said today at the event.

The company offered the service as an experimental feature for Android last year.

"This has been one of the most requested features, and is coming soon," Ms Chen said.

Mr McClendon said an Apple version of the service could be added in the future.

Google also announced improvements for Street View, which features photos of roads and byways around the world.

The company, which has mainly relied on people in autos to capture the images, said today that it will incorporate images taken with other devices.

Bloomberg