If you're seeing "~X mins/hours/days", it notes how long it has been since the location was last updated for that friend. For instance, if you're seeing "~1min," it means that the location was last updated 1 minute ago and has not been updated since.
There may be several reasons why a location is not being updated in real-time, including bad internet connection, low battery, and Doze mode (when an Android device has been stationary for a long time). To improve location accuracy, please visit this page.
Alternatively, "Now" means that your friend is currently there and their location is updating properly.