Kindly note, the SBB website is www.sbb.ch/en.
The Swiss Travel Pass is not available for purchase in the app, it can only be purchased from the SBB website. Before buying it, create an account first, then buy the STP while authenticated. Download the app and log in using the same credentials as used for the website’s account. The STP will be synced with your app, it appears as a ticket there.
Whether you buy both passes with one account or with two accounts, or if you have it on the same device or on two, is your decision. The same user account can be used simultaneously on three mobile devices. Consequently, you can buy it with one account, and later you both use the same account on your individual mobile phones.
There is no need to create an account. You can also buy the STP as guest and show it as PDF on your phone. However, buying as a guest will have the downside that your STP is not available in the app.
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