I love my S4 but I found I was not getting the accuracy I had been using Swype. At +Martin Guay 's suggestion, I tried TouchPal X on my Note 8. I was looking for a keyboard I could use with one hand and this one fits the bill well.
The neat thing about this keyboard is all the options. You can swipe or tap and flick words down to the spacebar once enough letters have been chosed and you can choose from the word suggestion bar. The keyboard does learn from your use and twitter feed and, like most keyboards, you can add words to the dictionary. Plus, themes!
If you want to try something different, try this free keyboard.