How To Enable iOS 6 3D Maps On iPhone 4, iPhone 3GS And iPod Touch 4G

Note: You need to first jailbreak iOS 6 beta on your device using Redsn0w. It must also be noted that you should download iOS 6 beta legally from iOS Dev Center only.
Step 1: Download the required .deb from the source site here.
Step 2: Open a terminal app on your device or through SSH, and then type the following:
apt-get update
then
apt-get install mobilesubstrate
Step 3: Next, load the .deb file onto your device in /var/mobile via WinSCP (Windows) or Cyberduck (Mac), before entering:
cd /var/mobile
dpkg -i  com.alpden.3denabler_1.0_iphoneos-arm.deb
Step 4: Ensure you respiring (or, to be safe, reboot) in order for the changes to take effect.