These options are only available in the professional package or if you have activated the API module separately on your LeaveDays database.
For all Professional users of LeaveDays.com there is an API connection available from which other applications can be linked to your LeaveDays system. In other words, the linking technology is available. You just have to build the link yourself. The documentation on this API, along with the neccessary client-id and client-secret (which are further explained within the documentation) can be requested through the LeaveDays support team. They will supply you with the requested information as soon as possible.