On Virgin Mobile, you're in a bit of a pickle for phone selection. This Sprint prepaid subsidiary offers a ton of entry-level Samsung and LG devices that aren't very good, and the Galaxy S III, which is still pretty good. However, the Galaxy S III sells for $399 (currently on sale for 15% off). It's more expensive than other carriers, so it's probably not worth it. If Virgin Mobile is your prepaid carrier of choice, take a look at the Virgin Mobile Supreme.
How to enter code for ZTE Supreme, Virgin Mobile Supreme, Vital:
1. Insert foreign (not accepted)* Sim card
2. The phone should ask for unlocking code
3. Enter NCK or Network code
4. The phone is now unlocked
*NOT ACCEPTED : means, to use a sim card from a network other than the network your ZTE is locked to.
Unlocking ZTE Supreme, Virgin Mobile Supreme, Vital, by code is very easy, it is also safest and non-invasive method of unlocking your phone permanently.
Here is the link that will give you the answer to all your questions about the Virgin Mobile Supreme. I almost bought the S3 until I found the Supreme and compared specs and reviews. If you are a Virgin Mobile customer like I am and want a great Android phone that blows the rest of the big names out of the water both by specs and price, this is definitely it! You'll be wasting your time and money looking at anything else.
Universal USB Car Auto AC Charger Power Adapter for Virgin Mobile ZTE Supreme