Please make a free trial version
I just tend to be really harsh on apps (just too many bad ones out there) and I would like to try this app before spending the $4.99 and end up with something that I use for 30 seconds, leaving bad feedback and then deleting. Having a free version would really help.

We fully sympathize with this.
Unfortunately Apple does not provide a good solution for this now. We would need to make either a dumbed-down free version or an in-app-purchase driven version. In either case, we’ve still got the problem that whatever doesn’t come for free must still be tried out only after payment.
In addition, distaste for the whole free download (and your personal information is the product) plus in-app-purchase philosophy aside, dividing features and/or apps like this would consume our resources that we’d rather put towards improving the keyboard.
Please send feedback to Apple requesting that they add a time-limited trial feature.