You are able to upgrade your plan within App Radar at any time. You can either click on the "Upgrade" button on the top bar or access your "Settings > Plan & Upgrade" (top bar, right corner).
To downgrade your plan, you need to access your "Settings", and then go to "Account Settings." Below the"Update Profile" button, you need to click on "Deactivate Account." As soon as you do that, you will have the chance to choose between downgrading your account our deactivating it.
If you need further information, contact us at support@appradar.com