Well depending on if you signed a contract for the device you have a few solutions.
First you buy the android phone at full price, then swap it on your account for the iPhone.
You can also buy an android off of the internet for a cheaper price, but of course that could be risky.
You can also inquire about Verizon's payment program. You buy at full price spread over time payments.
A friend or relative may have an android phone you can use or keep, then again just swap it out.
Lastly if you decide to go to another provider you may get a phone of your choice at a reduced rate or on time payments.
However only T-Mobile at this time is paying off early termination fees and buying back your old iPhone. However you will need to buy a new device from them. Also be alerted that the service may not be good for you. Check coverage.