Very neat. I'm the kind of person who likes having everything laid out before him, i.e. I don't like organization that relies too much on depth. For example, I usually prefer prefixing my file names rather than splitting them into subfolders.

It's a version 0.0.1, so here's my 2 cents: the only thing that really bothers me is the menu. The whole UI is quick and responsive, but this menu opens very slowly. The thing is, I don't think you actually need it. Why hide tools that users will probably interact with a lot? There's so much space in the header, left to the logo. Just put the buttons there and forget about the menu.

You're not the only one I see making this "mistake": not appropriately using the space available, especially when there are only a few elements to show. The greatest misuse I see is dropdowns [1]. On a personal level, I hate them (because, like I said, I prefer having all my options available before my eyes). But on a more general level, dropdowns are often used for a few items only, and remove any sense of hierarchy. They're just hidden lists of frequently-used options, put on the same level of importance.

To give an example related to your app: "add item" is on the same level as "email". But the former is both frequently used and non-penalizing (you can undo it easily), whereas the latter is rarely used and makes you leave the app, which might make the user lose some valuable data.

[1]: http://jgthms.com/dont-use-dropdowns-for-a-few-items-only.ht...