Starting in version 5.1 on iOS and macOS, Saved Places has returned.
iOS
This can currently be done from the Today view on iOS. Tap the addresses below the Map and choose an address to name.
This can also be done in the Filters menu. Tap the magnifying glass at the top of the screen > Places > and choose a location to name. Tap the Places tab to see named locations.
macOS
In an entry, click the location at the bottom and choose Name Location.
