TeleNav has unveiled AT&T Navigator 1.5i for the iPhone. The latest revision to the popular turn-by-turn GPS app includes road speed limit signs, speed limit alerts, and improved route avoidance options that account for high occupancy vehicle (HOV) lanes and toll roads.

The app also finally includes a nighttime map mode, an improved pedestrian mode, and the ability to return to the origin of the last trip taken via the Recent Places Menu. Finally, AT&T Navigator 1.5i includes Shake-to-Go, which lets users shake the iPhone in order to instantly cue up a route back home.

I've been testing 1.5i over the weekend. So far it has crashed a couple of times, but the speed limit indicators were accurate across an 80 mile round trip, and the nighttime mode looked sharp.

I also noticed something odd with both AT&T Navigator 1.5i and the TomTom app: both of them continually lost position in eastern Massachusetts (near Boston), to the point where they were unusable, on my own iPhone 3GS. Both of these apps were quite accurate during my PCMag.com reviews last summer (on a different, loaner iPhone 3G). I'm currently investigating the issue.

Source: TeleNav Improve...