I have upon iphone 4 and I'm wanting to switch to an android which one do y'all prefer
LOL, you're probably going to get as many answers as there are Android phones out there I prefer the Nexus line of phones, I know people who are die hard Samsung, HTC & Motorola fans. We all have our reasons, but what it boils down to (and what my advice to you will be) is we all have the phone we liked the most. So consider the current offerings, read up on what people like/dislike about them, see how that matches up against what you want in the phone and get the one you feel you can live with.
*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
I agree with dmapr in that your question is a bit too broad to give an answer to. I could answer based on my preferences, but that would still be a lot of devices. The devices beneath my avatar show less than half of the Android devices that I own, and I like different things about each of them.
Why do you want to leave an iPhone and switch to an Android phone? If you like the way iOS looks but want a larger screen and some additional features, a Samsung Galaxy S4 may be suitable for you. If you like the build quality of the iPhone, an HTC One may be suitable for you. If you want to leave an iPhone because you are tired of the small screen, a Samsung Galaxy Note II may be suitable for you. If you are tired of carrying the same phone that millions of other people carry, you may be interested in the LG Optimus G.
If you list more of your preferences, along with things that you can't do now but wish that you could do, it would help us give you more informed opinions in your search.