The app uses the time zone in use for your device.
When creating a poll with time options using the app, time zone support is automatically enabled. The poll uses the time zone that the user set in his phone or tablet settings. It happens all automatically.
If a participant opens a poll with time zone support in the app, a message is shown if the poll uses a different time zone than the one set in the device settings.
The times are automatically converted to the user time zone (according to the phone or tablet settings).