On the Web
Click on "Upgrade to Pro"
In the payment page, enter your coupon in the left panel
On iOS
Click on "Get Pro" / "Pro" / "Business" on top of the app screen
Click on "Help"
Click on "Redeem Code"

On the Web
Click on "Upgrade to Pro"
In the payment page, enter your coupon in the left panel
On iOS
Click on "Get Pro" / "Pro" / "Business" on top of the app screen
Click on "Help"
Click on "Redeem Code"