The one ball rule will not be in effect for the championship. All equipment used during the event must be USGA conforming. It is the player’s responsibility to determine conformity. Any player using non-conforming equipment will be subject to disqualification. Electronic Measuring Devices will be allowed during play, as long they measure distance only.”
Be certain that the App used is conforming, it should display on the App or be clarified in the App’s details and settings, etc. If you cannot confirm on the App itself, reach out directly to the App you used for clarification.