I am having this same issue. I'm trying to use the web version of Evernote and the delete key does not work. I am on Mac El Capitan, using Chrome. I cannot replicate the problem in Firefox - so it looks like a Chrome/Evernote issue. Not all notes are affected, but if I copy and paste a note's contents into another note, the behavior is the same (delete key does not work).
Can you provide an older version apk for us to download? I really need this feature for my note taking during meetings.