I have an mid-sized(ish) app that plots a user's home address on a map, along with a number of locations. Those other locations are also displayed in a list. Each location has the distance from home displayed in the list.
Currently, distances are calculated as the shortest distance between two points (as the crow flies). I want to add a feature that will give users access to actual driving distance & time. Trouble is, calculating driving distance/time on load will max out the free quota with 100 items in the list and 25 users/day.
The only thing I've thought of so far is calculating the straight-line distance by default and adding an element to each item in the list that allows users to choose which items they want real distances/times for. I can see potential challenges when they update their address (do we keep calculating travel distance for ItemX because they requested it once?) but it would go a long way towards limiting the number of calls we make to the google api.
Has anyone else run into a similar challenge? How have you handled it?