Duplicate the location structure for journeys.
journey model data is two locations
in edit mode the user should be able to select two different locations for each end of the journey (ie no text fields needed but instead some menu of locations from the Locations collection
otherwise ui should be similar to locations
Having thought about this some more, I guess it should work slightly differently to the location/locations. The journeys view is the main view for the app - the first view to be displayed. The main purpose is to allow the user to retrieve a set of 'routes' for a single journey. So, the UI should present the user with his/her configured journeys (location/gps -> location), and the action of tapping one of them should caused the route to be resolved and displayed.
So, the edit/new functionality needs to be different to the journeys view.
I agree, though they would be closely related. I think we should give the possibility to create a new location too, in case it hasn't been memorized yet.. Or in case the user just wants to know how to get somewhere without saving the destination..
I guess there's a case for having a one-time destination. Perhaps we could add that later since we seem to be having trouble with even the basic functionality.