Re:I Hit $115k/Month with a Status Quo Improvement
by ajaygoel on Wednesday February 20, 2019 @10:37PM
(#19214321)
The user logs into his Gmail account on his own and uses the GMass extension, which operates within the Gmail UI, to create/schedule campaigns. On the back-end, GMass connects to the user's account over standard Google OAuth 2 to then send the emails.
I am assuming you mean you send from the client UI but the extension talks to your server for scheduling the future sends etc. in which case you shouldn't have that much network bandwidth.