Platforms: iPhone, Android
With the release of iOS 8 you can now use 3rd party keyboards. Minuum was the first one I downloaded and I really like it. It has a regular sized keyboard with predictive words on top. Very similar to the stock iOS keyboard but the magic comes when you slide your finger down the keyboard minimizing it. It looks like this:
How can your fingers possibly hit the letters you want? Minuum guestimates which letters you tried to press and puts the words it thinks are most likely on the suggestion bar. It is surprising how well it works.
So why would you want this? For me the added screen real estate is the biggest reason. I have an iPhone 5s with no plans to upgrade and regular sized keyboards take up so much screen space that it’s hard to get a full sense of what you’re writing. It's funny, I thought I'd be using swipe based keyboards as soon as iOS 8 was released but Minuum really hooked me.