DejaLu - a new open source email client by Sparrow's author

I downloaded the beta and gave it a try.

At this stage, it’s already a better email client than Airmail.

Some notes:

Amazing startup speed. Why can’t all apps be like this?
Nice and clean UI. Community themes could be a great feature to have but I don’t mind not having it.
I specially like the conversation list view. It’s just so clean.