Google's awe-inducing, turn-by-turn Maps Navigation is exclusive to Verizon's Droid phone—unless you're willing to hack around with your G1. With either some command-line-fu or a two-part Windows application, you can put Google Maps Navigation on a rooted G1.
By 'rooted,' we mean a G1 running the latest Cyanogen custom ROM (and here's the wiki guide to installing it). Installing this hack, like rooting your phone, totally voids your support options from T-Mobile or other provider, and we can't recommend backing up your G1 highly enough before you launch on this endeavor.
Having said that, I've managed to get Navigation on my G1, following the step-by-step instructions at the second link, with the Android developer's SDK installed and using adb --help to figure out what I was doing. Gizmodo recommends a batch file that does the dirty-but-quasi-legal work for you, including installation of the Maps/Navigation app from Android 2.0 (which I grabbed from this thread, registration required).
Update: Some users in the xda-developers forums and elsewhere are seeing the Navigation option vanish upon reboot, or when trying to replace their build.props file to escape glitchiness. We'll update this post with any long-term fixes when we find them.
Here's a little video reminder of what Google Maps Navigation does—in short, web-attached, turn-by-turn, voice-recognizing driving directions:
Got Navigation working on your own G1 (or, even better, other Android phone)? Tell us what you like, or any quirks you encounter, in the comments.
Original step-by-step terminal instructions [XDA-Developers Forum]
.jpg)
