If you're an iPhone or iPad user who also uses Microsoft's Office 365 platform, then the newly-released Hub Keyboard for iOS is well worth taking a look at.
What's special about the Hub Keyboard is that it allows you to get stuff done directly from the keyboard, which means that you spend less time switching between apps.
The Hub Keyboard has three tricks up its sleeve:
It allows you to easily insert previously copied text without having to mess around with the iOS cut/copy/paste user interface
It offers the facility for searching for OneDrive and SharePoint documents so you can send links to them to others
It allows you to access both the contacts from your iPhone and your Office 365 account
If you're not an Office 365 user then there's probably not much to draw you into using the Hub Keyboard (other than perhaps the ability to insert copied text), but for those who use OneDrive or SharePoint, this is well worth a look.
I have noticed a problem, though. Specifically, the keyboard is slow to bring up, but this is a complaint that I'd level against pretty much every third-party keyboard for iOS I've tried.