I'd love any easy way to stamp (type) in the current date & time.

That and be able to see a per-item timestamp on an element in the outline. I suppose this would lead to having both a created and a modified timestamp.

But a quick timestamp macro would be great in the meantime.

The web version is too small and not practical to use on an Android phone. Can you either make an Android App or make a mobile version of the website that adjusts to the users device.
There are now more Android users in the world than iOS. Please take our money.

Mindmap / PDF / Markdown ...

An autosave feature

If you have more than a few outlines, you'll really need to group them into folders. CarbonFin Outliner doesn't currently support folders in Dropbox.

So the storage location defaults to Dropbox.

It would be nice if one could add priorities to tasks and sort tasks by priority.

Add a radio button to options, or modify Archive, to protect an outline from being inadvertently deleted. This happened to me when I was trying to deconflict a file on my iPad with one on my iPhone. I inadvertently swiped a similarly named outline and the sync process deleted it instantly on both devices with no way for me to undo that deletion. I lost an outline representing the entirety of my work in the month of June! With a protect mode, it would at least give me a question for verification.

support for copy and paste in the desk version, just like in the ipad version.

As it is now reducing font size ("small font") doesn't reduce line height. This is not terribly useful.

With "small font" also line height should be reduced (and accordingly the size of the triangle and checkbox).

I would prefer the following format: I.1.A.i.a. etc vs the current legal format.

I use master lists (eg for food shopping). I check the items I need then uncheck them when bought. A filter to show only checked items will reduce as I buy items but my master food list is retained.

Search / Finde in Outliner Online
I also use Outliner Online a lot on my desktop, what I realy mis is a search/find function in the Online version, would be great.
Ctrl-F browser function doesn't work unless all's expanded, but then one has no overview on the outline

hello.
i think that it is more suitable that "sync evernote" than "sync dropbox"
because dropbox is just cloud but, evernote is note and cloud. and outliner is not file, NOTE!

plz, sync evernote like "cloud outliner" that sync evernote

plz!!!!

Would be nice if one could round-trip OPML files between CarbonFin and Outlinely (OS X) - http://glamdevelopment.com/outlinely

Right now whether an item is a "status" or regular node and if a status is "checked" or not is not be preserved between the two products.