The accuracy of the location from the iPhone improves over time. The reason for this is that it needs some time for the GPS sensor to receive information from the GPS satellites. Add a label to the DistanceViewController that shows the accuracy as long as no location is stored. The accuracy is delivered in the CLLocation instance.
Add a label or an alert that informs the users that they have to leave and reenter the 10-meter radius after they have set the anchor.
Let the user type in the text that is drawn on the ground.
Change the world mapping status text shown to the user. Make it meaningful for the user.