iOS 8 will allow users to install systemwide third-party keyboards
Apple has just announced at WWDC 2014 that as part of its iOS 8 extensions capability, users will be able to install systemwide keyboards, such as the popular Swype system. The keyboards will run in a secure sandbox and not have access to anything except text input, though they can ask for permission to use the network in order to provide more features.
These keyboards can be installed through third-party apps on the updated App Store.