When you click on the PK4 TimeTracker oAuth tile from the App Launcher, you'll encounter a Thank You page as depicted in the image below.
Unlike other applications, TimeTracker utilizes this tile to acquire oAuth privileges for utilizing the PK4 TimeTracker application within Salesforce.
A single click on the tile suffices, typically during the initial installation of the PK4 TimeTracker app in your org. Subsequent clicks on the PK4 TimeTracker oAuth tile result in re-authorization without any additional impact, and the PK4 TimeTracker app continues to function as usual.