While using APG iPreflight data, is it mandatory to use the V1 speeds listed in the app (TOLD card)?

Yes. The takeoff limit weights provided by APG are only valid when using the V-speeds and level-off height specified in the TOLD (Takeoff and Landing Data) card. Deviating from these speeds—especially using a significantly different V1—may compromise the aircraft’s ability to meet required obstacle clearance and performance margins. For safety and compliance, always use the speeds published in the TOLD card.