Nothing should be done by you to adjust the Daylight Saving Time (DST) on a mobile device.
By default, Android or iOS devices (iPhone, iPad, etc.) will automatically adjust their time for DST based on the cellular provider's network. If using a Wi-Fi only device (e.g. tablet without cellular service), it will receive its time from the internet.
Please note: If employees are working during the DST time change, this will require manual adjustment on the employees respective time card.