This app was mentioned in 9 comments, with an average of 1.22 upvotes
Personally, I use the stock Xperia keyboard that my phone came with. Sometimes the swipe doesn't respond as well as I'd hoped to, but it learns really well and it's pretty smooth overall.
https://play.google.com/store/apps/details?id=com.sonyericsson.textinput.uxp
Keep in mind that it wont work on all phones.
You can change height, color, even one handed mode
Op, here's the play store link for it.
https://play.google.com/store/apps/details?id=com.sonyericsson.textinput.uxp
Don't know if you can still download
Try installing it from here. ;)
Is this what you're after?
Or the Xperia Keyboard
It's in the play store...but I'm not sure if it's restricted to Sony phones or something.
https://play.google.com/store/apps/details?id=com.sonyericsson.textinput.uxp