Google Latitude has just been updated for the iPhone. This update brings the ability to check in to restaurants (rivalling services like Foursquare) and brings an improvement to battery life when running in the background.

What’s New In Version 2.1
— Check-ins: Check in at places like restaurants so your friends can see you’re there.
— Improved battery use when background reporting

Latitude is a useful app for sharing your real-time location with friends and family, when you need to. The original release had extensive battery draining issues. The native app was released into the App Store last December, as previously it was a web-only app. Click here to download it.