Hello Cevaisha88
This is not possible. The Swiss Travel Pass cannot be added to the SBB Mobile App, same applies for other tickets that were bought from a third-party supplier.
You are welcome to present your Swiss Travel Pass as PDF on your phone. A printed copy is always helpful in case your device has no more battery.
Please kindly note, the Swiss Travel Pass is only valid in combination with your physically available passport, or your official ID card, or your driving licence; they must be presented together upon ticket check.
Kind regards,
Roland