More Icons is a tweak available on Cydia that allows you to choose how many rows and columns of icons to display on the SpringBoard (the home page), so you can display a fifth row of icons to a resemblance iPhone 5.
After installation, go to the Settings tab and open the More Icons. You will then have various options to change the number of columns or rows. You can also change the spacing between each icon. tweak is compatible with the iOS 6.1 More Icons is available for $0.99 on the repo BigBoss .