You can redeem your license key by clicking on the ‘License’ button located in the settings of the apps under the ‘Other’ section.
Please just note that you will need to enter your license key in all of the apps that are part of the it Toolbox because we currently don’t have a way to validate the license outside of the app the license key was redeemed in.
Please also note that you can only redeem your license key in the macOS versions of the apps that are downloadable from our website here: https://www.designtech.so/it-toolbox. Your license will be automatically synced to your other devices for the given app as long as you have enabled the iCloud functionality for the given app and logged into the same iCloud account.