The acknowledgement feature has been designed to clearly highlight to your team whether a visitor has read and understood the next steps (e.g. your action) see the article What is an action?
This feature is enabled by default for all check ins and works in the following way.
When you select the appropriate next steps for your visitor to follow (e.g. your action) your visitor will receive a pop up on their device informing them of next steps with ability to press ok, similar to the example below.
Until your visitor acknowledges these next steps by pressing Ok the visitors card will be marked as Awaiting Response, see below for an example.
Should the visitor press Ok the check in would be regarded as acknowledged, meaning they have read and understood your instructions. You can see that the client has acknowledged your instructions by looking bottom left on the visitors card, below is an example.