Browser for schedules of conferences like SHA2017, FOSDEM, CCC/35C3, LCA 2018 (linux.conf.au) and many more. (Supported formats: Pentabarf/Frab/xCal/iCal)
It lets you organise your visit - select talks to be reminded of (with warnings in case of conflicts) or hide the topics you're less interested in. Schedules are shown in whatever format you like - block schedules, plain timetables, or a clear now-and-next screen on the day itself.
Or just put a widget on your homescreen which will always show you what's next.