Sell your smartphone yourself on Ebay or Craigslist, or buyback companies such as Gazelle, Glyde, Amazon, BestBuy, and Apple. Some pay with cash; some pay with credits.
Phablet vs smartphone question; the phablet versatility is because of a larger display than a smartphone; tablet strengths and limitations are considered.
This smartphone review is the Samsung Galaxy S4. It has 16, 32, and 64GB versions with LTE. The S4 has a 5-inch display, among other great features.