You can view the keyboard shortcuts that our Polymail macOS app supports anytime, by hitting CMD + "/" or by going into the Keyboard Shortcuts option under the "Help" menu. 

If you're familiar with Gmail shortcuts, we also support those! 

Here's a quick list:

Keyboard Shortcuts Guide: ⌘ + /

Thread Actions
Read Later: ⌘ + D
Move to Archive: E
Move to Trash: ⌫ (delete)
Move To Inbox: ⌘ + I
Move To List: ⌘ + L
Unsubscribe: ⌘ + U
Undo: ⌘ + Z
Toggle Read Status: ⌘ + ⇧ + U
Toggle Star: ⌘ + ⇧ + L

Compose Actions
New Draft: C
Reply: R
Reply All: A
Forward: F
Follow Up Reminder: ⌘ + Y
CC: ⌘ + ⇧ + C
BCC: ⌘ + ⇧ + B
Send: ⌘ + ↵
Send and Archive: ⌘ + ⌥ + ↵
Send Later: ⌘ + ⇧ + ↵
Add Calendar Invite (while composing): ⌘ + ⇧ + E
Copy Polymail Calendar Scheduling Url: ⌘ + E
Message Templates: ⌘ + ⇧ + O
Discard: ⎋ (esc) or ⌫ (delete) when in Drafts 

Other Actions
Search: / (forward slash)
Toggle Right Sidebar: ⌘ + \\ 

Navigate to Mailbox
Inbox: ⌘ + ⌥ + 1
Read Later: ⌘ + ⌥ + 2
Starred: ⌘ + ⌥ + 3
Archive: ⌘ + ⌥ + 4
Trash: ⌘ + ⌥ + 5
Sent: ⌘ + ⌥ + 6
Send Later: ⌘ + ⌥ + 7
Follow Up: ⌘ + ⌥ + 8
Drafts: ⌘ + ⌥ + 9

Other shortcuts:
Toggle Command Control: ⌘ + J
Copy: ⌘ + C