Two considerations that help avoid the IP issue, but require user permission and so have a big obvious disadvantage: 1) We can prompt mobile users to enable lo

Two considerations that help avoid the IP issue, but require user permission and so have a big obvious disadvantage: 1) We can prompt mobile users to enable location/gps and get their location that way. 2) We can prompt modern browsers to allow location services and get their location that way. This is if a user wants to have their location 'auto-set' instead of via pulldowns. 3) A hard problem to solve is - mapping a unified set of city names to timezones, and updating the timezones as per Daylight Savings Time and general timezone updates. Anyone have references for 3) ?