You can change your phone's time zone through the Settings app on both Android and iOS devices. On iPhones, open Settings, tap General, select Date & Time, and toggle off 'Set Automatically' if enabled, then tap Time Zone to select your preferred region. On Android, go to Settings, navigate to System > Date & Time (or similar, depending on your device manufacturer), turn off 'Automatic time zone' if it's on, and select your time zone from the list. Most modern phones default to automatic time zone detection using GPS and network data, which updates your time zone whenever you travel. Turning off automatic adjustment gives you manual control, useful when you want to keep a specific time zone temporarily or when your phone's automatic detection fails. Some phones also let you set a custom time offset if your exact time zone isn't listed. After changing the time zone, you'll notice your clock updates immediately, and any calendar events or scheduled notifications will adjust accordingly based on your new time zone. If you're traveling frequently and keep changing zones, you might prefer leaving automatic time zone on for convenience. Some apps also have their own time zone settings in their preferences, so check individually if those aren't responding to your system-wide change.