Estimating times to leave and to travel

A data processing method comprising:

• using a server computer, obtaining from one or more non-transitory computer-readable data storage media a copy of one or more sequences of instructions that are stored on the media and which when executed using a particular user computer among a plurality of user computers cause the particular user computer to perform:
• using the particular user computer alone or in combination with the server computer, obtaining a present location value indicating a present location of a computing device and event data indicating an event location and an event time;
• determining a route of travel between the present location and the event location for a mode of transportation from the present location to the event location;
• determining one or more route segments in the route of travel;
• determining one or more estimated journey times respectively for each of the route segments;
• adding one or more padding time values to each of the route segments;
• determining a total travel time based upon the journey times and the padding time values for all of the route segments;
• determining a recommended time to leave based upon a current time and a difference between the event time and the total travel time;
• using the server computer, downloading the copy of the one or more sequences of instructions to any user computer among the plurality of user computers.

A computer system comprising:

• a server computer comprising one or more non-transitory computer-readable data storage media stored with one or more sequences of instructions which when executed using a particular user computer among a plurality of user computers cause the particular user computer to perform:
• using the particular user computer, alone or in combination with the server computer, obtaining a present location value indicating a present location of a computing device and event data indicating an event location and an event time;
• determining a route of travel between the present location and the event location for a mode of transportation from the present location to the event location;
• determining one or more route segments in the route of travel;
• determining one or more estimated journey times respectively for each of the route segments;
• adding one or more padding time values to each of the route segments;
• determining a total travel time based upon the journey times and the padding time values for all of the route segments;
• determining a recommended time to leave based upon a current time and a difference between the event time and the total travel time;
• in the server computer, stored downloading instructions which, when executed using the server computer, cause downloading a plurality of copies of the one or more sequences of instructions to the plurality of user computers.