Spell Check Does Not Exist on App for Chromebook?

I love the simplicity of K-9 Mail and the fact that is a free open source platform. However, there is one very important, basic feature that is missing. Spell check is a fundamental must, but K-9 does not have it, at least on the platform I am using it on… Android on Chrome OS/Chromebook. Is there something I am missing, or does spell check indeed not exist for this app on Chromebook?