This feels right for the most part.
I like the Google Drive approach but am a bit disappointed, that I cannot view my data there. This would be data export by default and thus awesome.<p>Export is really important to me to feel safe. Also I'd like to know the business model, which I assume is freemium.
The preview has no undo, and ctrl+a and del is one of the first things I did. It works in the app though.<p>Maybe, you could implement some kind of incremental ctrl+a, so that it first only selects the item you're in - though there are already other shortcuts for that.<p>Long texts will be broken up into multiple list items each time you use enter. I am not sure, if that can lead to problems later on. So far it does not.<p>Very well executed, including apps for iOS and Android.