To enable this feature, use SwiftKey and type "tilt", long-press the prediction and tap on SwiftKey Tilt and there you have it, a pinball on your keyboard. Now you can start using SwiftKey Tilt. I like how they already hid this feature beforehand so you don't even need to update. The only downside is that in order to enable SwiftKey Tilt, you have to type "tilt" every time, which I hope they remove with a future update.
Happy April Fools' from SwiftKey!
Source: SwiftKey's Blog