Add Tracking Feature that's in the iOS version
There is a tracking feature in the iOS version of this program. Add it into the Mac Application version.
You can enable read receipts via a plugin on the main website if that's what you need.
Seriously - at first I thought I just wasn't able to find it but quickly realized that it's not in the desktop version. Find myself "Saving as Draft" and then sending from my phone to enable tracking. Seems like a no brainer to add this to the desktop version!