Time differences and daylight saving
Each card shows the difference from your device’s time, for example 7 h behind you. The difference is worked out from the time zone rules in force right now, so it changes automatically when a country moves to or from daylight saving time. That is why the gap between Jakarta and London can be 6 or 7 hours depending on the month.
Indonesia does not use daylight saving time and has three time zones: WIB (UTC+7), WITA (UTC+8) and WIT (UTC+9). All three are in the city list.