Playing around with iOS 8 I was going to install SwiftKey. But, ran into an issue with the warning to install the keyboard - they collect every key you type. This creates quite a conundrum for those in the healthcare world.
Why? Simply put you don't have a BAA in place with SwiftKey, nor do you know if their infrastructure is HIPAA/HITECH compliant.
So, while I assume SwiftKey is on the up and up, you simply must avoid it if you are in any type of field that requires any type of compliance.