Hopefully I'm not reading too old of a thread here, but I have relevant info.
Last year (2013) Cricket put all Android smartphones on sale for 50% off -this included even the (at the time) just released Cricket-enabled Galaxy S4. If I'm not mistaken, Boost Mobile and/or MetroPCS did something similar too.
I've been looking out for a similar deal, since Cricket basically screwed me over a few months later by announcing that my brand new phone would get less than two years of service before they cut off support of the model completely. (Switching to GSM from CDMA with no transition deals for current customers seems like a great way to lose your customer base, but At&t has made similar mistakes when purchasing other cell providers in the past)
Anywho, I've seen "deals" for some of the more major providers show up in ads like Walmart for black Friday, so I would check there. They seem to all be pretty basic contract renewal deals though, nothing too special tbh.
Personally, I'm looking into a switch to MetroPCS: They operate on T-Mobile's network, but for $70/month I can get truly unlimited 4g(I believe LTE too if I'm not mistaken). Users have been testing it for more than a year, and are getting well into the hundreds of gb without being slowed down...