SwiftKey Flow review: The Android keyboard you've been waiting for

One of the coolest things about Android is how flexible and customizable the platform is. You can replace practically any part of the system with a third-party alternative; you're never stuck using something just because that's the way it ships.

There are few better places to flex that power than with the on-screen keyboard. While the stock Android keyboard is certainly not bad -- and has actually gotten quite good, with the changes introduced in Android 4.0 and more recently 4.2 -- there are plenty of interesting alternatives available. And one of them just got very interesting.

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I'm talking about SwiftKey Flow, the new beta version of the popular SwiftKey keyboard released this morning. SwiftKey Flow adds support for gesture-based typing, which means you can type by sliding your finger from one key to another without lifting it off the screen.

The app is currently available as a free beta download from SwiftKey's website. SwiftKey has yet to announce whether the final version of the keyboard will be integrated into its existing apps or sold as a separate application.

SwiftKey Flow: A powerful typing package

The concept of gesture-based typing isn't new to Android, of course, but the combination of that functionality with SwiftKey's already-excellent interface and word-prediction technology packs a powerful punch.

SwiftKey Flow's slide-to-type feature is incredibly accurate, rivaling the likes of veteran Android gesture-typing app Swype and the native gesture-typing functionality in Android 4.2. In my early tests of the app, I've struggled to produce many errors at all; even with sloppy swiping, SwiftKey Flow does a tremendous job of figuring out what you're trying to say.

While the basic slide-to-type method is the same as what you see in other applications, SwiftKey Flow does add in a significant new twist: When inputting with gestures, you don't even have to lift your finger between words. You can simply swipe down to the spacebar, then swipe back up and move into your next word -- allowing you to type entire sentences without ever stopping.

I've found the continuous-typing feature to work impressively well, though it does take a little practice to get used to the motion. The good news is that you don't have to use it; you can just as easily lift your fingers between words and do a more traditional slide-to-type movement if you'd prefer.

SwiftKey's word-prediction system is fully integrated with the new Flow setup: With longer words in particular, the app will often figure out what word you're going for before you finish inputting it. When the word you want appears above the keyboard, you can simply stop swiping and the app will fill in the rest.

SwiftKey Flow uses its standard intelligent-prediction technology to guess your next word, too, with three choices appearing in boxes above the keyboard every time you stop inputting text. Its best guess sits in the middle, and like with the regular SwiftKey app, you can tap the word or just press the spacebar to have it instantly inserted into your sentence.

SwiftKey Flow: More than gestures

So that's the new slide-to-type element of SwiftKey Flow. As I said earlier, though, what really makes this app stand out is the combination of the gesture-typing feature with all the stuff that made SwiftKey so good in the first place. SwiftKey has always been one of the best options for regular tap-based Android typing, and the new Flow version is no different in that regard; you can switch between swiping and tapping seamlessly, and both experiences are top-notch.

SwiftKey's user interface is also a strong point, both from a visual and a functional perspective. On phones and tablets alike, the keyboard is clean and easy on the eyes (and themeable, too), with large, easy-to-press keys and plenty of on-screen functions.

Those on-screen functions make a huge difference. While I've enjoyed using Google's own gesture-enabled stock Android 4.2 keyboard, its setup is a bit sparse in on-screen functionality. Almost all of its special characters are hidden and require multiple key presses to access; on tablets, you have to toggle over to a separate panel of keys just to get to numbers.