Jira Cloud applications support custom time tracking providers. You can configure Timetracker as your Time tracking provider in Jira, to hide Jira time tracking options and only display Timetracker features so that the permissions and time tracking rules configured will be applied to all Jira users. To change your time tracking provider: 

1. Select Jira settings > Issues.
2. Click Issue Features > Time Tracking.
3. Choose the Timetracker app from the Time tracking provider dropdown.