xGPS is a free project aiming to bring a powerful and easy to use navigation software for the Apple iPhone© and iPod Touch©. It has powerful features like turn-by-turn directions, vocal instructions, offline maps support and even more. An utility called xGPS Manager (see below) is also offered to allow users to downlad maps on their computer and wirelessly upload them to their devices in a user-fashioned way. xGPS currently use Google Maps for the maps and the routing data. It means that it will work wherever there is Google Maps support.
xGPS Manager
xGPS Manager is a program that allows you to manage the data stored, gathered and used by xGPS.
More specifically, it allows you to:
* Download Maps (navigation and relief) from Google Maps, and send them to your device.
* Retrieve Maps from your device.
* Retrieve Tracking Data (GPX files), and map them.
In order to send or receive files, you must have a computer (Mac, Windows or Linux) and a wireless router.
On the device, under settings, place xGPS into Wireless Transfer mode, and connect to it from xGPS Manager, to perform the above operations.
It may be possible to do this without xGPS manager, and wireless router (more on that to come).
Download Link
xGPS Installation
This will guide you through the steps required to get xGPS running on your iPhone or iPod.
Preparation
You will need:
* iPhone, or iPod touch (1G or 2G) AND external GPS module, or;
* iPhone 3G.
To install xGPS, you will need a jailbroken iPod/iPhone. If your phone is already Jailbroken, begin installation. If it is not, and you want to jailbreak it,
Tutorials.
Installation
Installation Video
Overview
1. Install Cydia package, "xGPS" from apt.modmyi.com
2. Restart device.
Step by Step
1. On the device, launch Cydia.
2. Wait for it to load.
3. Tap Search on the bar at the bottom.
4. Search for xGPS.
5. If xGPS is not found, tap Manage on the bottom bar, then Sources. ModMyI should be in the list. If ModMyI is not in the list, tap Edit, then Add. Enter apt.modmyi.com. Tap Add Source and retry steps 3 and 4.
6. Tap the xGPS search result.
7. Tap Install, in the top-right. (If it says Modify, xGPS is already installed. If you cannot find it, check any programs which hide icons.)
8. Check that the data usage is acceptable to you, then tap Confirm.
9. Wait for it to install.
10. Return to Cydia.
11. Hold down the power button, until a "slide to power off" bar appears at the top of the screen, then slide it.
12. Once the device is off, hold the power button until the screen turns on.
Configuration
Settings may be accessed by tapping the spanner icon, in the bottom left of the screen.
Set Up Your GPS
1. Starting from the settings page, scroll down and tap GPS.
2. Tap GPS to use.
If you do not have, or do not wish to use, an external GPS module, choose Fake GPS (iPhone), or iPhone 3G GPS (3G).
If you have an external GPS module, connect it to the iPhone, then select it from the list.
Setting Up Your Home Address
xGPS has a helpful "Go Home" feature, so that you can never get lost again. This feature needs to know your home address. To input your home address:
1. Starting from the settings page, scroll down and tap Driving direction.
2. Scroll down and tap Home Address.
If you are in your Address Book, tap Address Book, find and select your own name, then select your home address.
If you are not, type your address.
Source:
xGPS
Forums 
