I'd also like this layout. It's what I'm used to in a mail client.

The two panes layout is nice when on a higher resolution widescreen display. But, the current setups are better when limited to 1376x768, like I am when viewing on my laptop LCD. I want both with a easy way to switch depending on which display I'm on.

This would really be great!

Such responsive client must have two panes layout!

Yes, please I would love a two pane layout. Maybe an option to move the folders / tasks to the left side of the window as well.

I vote for two panes layout. I would also like a more compact view with less blank space between email subjects. 

Well, there's already a two-pane layout (in Beta) but what I mean is a two pane layout side-by-side (not top-bottom).

Two pane layout (side-by-side) would be greatly appreciated!

This + email rules are some basic email client things imo.. You guys have a great client on your hands here, and a good exchange client for linux was really needed. Just waiting on a few (basic imo) features and I'd be totally sold on Hiri. Well techincally I already purchased it, but you know what I mean :P

Two paned but side by side - as opposed to the beta version of bottom...

2 panes layout + folders to the left would be great. There is so much space wasted when using Hiri on fullscreen and for email with big headers the opening emails at the bottom option is almost useless.

Pleeeese.

Especially on Ultra Widescreen looks ridiculous, e.g. attached

Otherwise awesome!

 This is a great email client. PLEASE make the side by side view. for widescreen workflow this is a must. tons of wasted screen real estate.

Lending my support for this as well. That would make this email client 100% awesome! 

Any news on this? I find the vertical 2 pane layout more productive.

Likewise -- most monitors are landscape orientation - the vertical layout (ie.one pane on top of another) isn't using the available real estate efficiently.  Also many of us have years of muscle/eye memory with that layout.

I think Hiri is dropped from development. There was no update for almost one year. They are just trying to get as much money as they can from this dying product with their sales.