I'll give Samsung credit where it's due—the stock keyboard on the Galaxy S5 is actually pretty nice. There's a dedicated number row that resides at the top (something that the Google Keyboard needs a hack to achieve), and various settings exist to make switching between languages a breeze.
But it's a bit hard on the eyes, unfortunately. The light-colored background can brighten up a dimly-lit room when you're trying to type something. This can actually cause pain in the eyes if you've been in the dark for an extended period of time.
Developer chanthoeunpen must feel the same way, because... more