Note: The AppLovin dashboard UI was recently re-designed.
You need the following information to link your account: SDK Key, Report Key, Zone ID.
SDK Key and Report Key: Click on Account in the lower left corner and go to Keys tab. SDK Key and Report Key can be found in the first two fields.
Zone ID: Stay on the same page (Keys) and click on App Discovery in the upper left corner. In the appearing menu, click on Zones. In the new window Zone ID is listed in the second column.