How to Install Already Purchased Applications on an iTouch or iPhone

Connect your secondary iTouch or iPhone to your computer using the Apple compatible USB cable. Wait for iTunes to open, or simply open it yourself. Log in to the iTunes account which made the purchase.  This ensures that the secondary iTouch/iPhone will pair itself with the iTunes account that is logged in to that computer, hopefully the one that has already made the purchase. This is necessary for later. 

The thinking behind this was that if you were logged into the original account when the purchase was made, then just by plugging in your secondary iTouch/iPhone and trying to drag over the applications it would not work, but by saying that this iTouch is also on the original account (momentarily), that it is also allowed to use the purchased content.

Eject the secondary iTouch/iPhone, and then proceed to open the "App Store" application. Locate the already purchased application, and select "Buy Now" on the top right, or the price first, then “Buy Now”.  Do not worry, this will NOT deduct money from your iTunes account.  Your Springboard will then appear, with a message stating: "You have already purchased this item. To download it again for free, select OK." Select "OK", obviously.  The application will proceed to install istelf. When completed, make sure to restart your iTouch/iPhone as to avoid crashing or freezing. 

To desynchronize the second iTouch/iPhone with the sole account, simply plug it in to another computer with the second iTouch/iPhone owner's account logged into iTunes.

You are done!