One Handed Keyboard brings back the wonder of typing on you iPhone 6 Plus like you used to on your iPhone 5s.

The app is the product of Calgary developer Stonelight Pictures, and puts a keyboard that’s the same size as the one found on the iPhone 5s on the iPhone 6 or 6 Plus, with a simple, large button that can shift the keyboard either left or right depending on your preferences, or just which hand you happen to be holding the device with at any given time. The software keyboard can also be themed with various color options, as well as translucency to hint at what’s behind, though changing these requires giving the keyboard full access.

The iPhone 6 Plus Gets A One-Handed Keyboard App, And It’s Glorious | TechCrunch

I don't have a 6 Plus, yet, and I can't speak for this app, but I can see apps like One Handed Keyboard turning into something of a cottage industry on the App Store. Good for this developer for getting his flag in the ground early.