Hi StackOverflow,
I am writing a simple reminder module for an application. This module will support one-shot reminders as well as periodical ones, for example, monthly reminders. The module must also behave correctly when the user travels across time zones: the reminder's alert goes off at the precise moment in absolute time that it was configured for. The user will be able to add and edit reminders. I have to design this feature from the user's perspective: what the user interface for the reminders is, and how they are configured.
Everythig's easy for for periodic timers that work in a single time zone. Just define a monthly reminder by specifying the days of a month. But things get tricky when periodical reminders meet time zone travel. Consider a user who sets up a reminder to fire every 10th of a month and flies across the globe. Chances are that the reminder will rather have to fire every 9th of a month, according to her local time zone. Worse even, if the reminder is set to fire every 1st of a month, then it may have to fire every... last day of a month, whatever that is.
The question is not how to program the correct behaviour, but rather what the UI for this feature should look like. If the configuration of the reminders is static, and a periodical reminder is defined by specifying the exact days of the month, then how do I present a periodical reminder, which may fire on the 30th one month and on the 31th some other month? How would you design the UI?
Currently I intend to just show the warning "In your current time zone, the reminder alert will fire one day earlier than configured.". Is it acceptable?
Thanks,
Yaroslav