THIS IS NOT ABOUT A WALLET IN SPECIFIC !
This is a general guideline for developing a spending wallet, by Bitcoin Design team. Is not about some app in specific. Based on these guidelines, BD team is talking with developing teams and help them with a good design. They did it with many wallet apps and all their talking sessions are public on BitcoinTV: https://bitcointv.com/c/bitcoindesign/videos
It's actually a design to allow developers to build their own open source wallet. I made that mistake myself during the first read:
A reference design is a complete design for a bitcoin product. It goes beyond just demonstrating individual user flows – rather, it shows you how all of the user flows fit together and serve a purpose in the user’s life. You can use this open-source reference design to help you build your own similar bitcoin product!
At some point, users are likely to either lose their mobile device, purchase a new one, or delete the wallet app.
For them to recover their wallet again, they would need the following:
The sign-in details of the cloud account that contains the backup key
The PIN they created when setting up the wallet, to decrypt the cloud key
Access to their signing device
They can use their PIN to unlock the cloud key and, with the help of the signing device, recover their wallet. If the user loses any 1 of these 3 things, they will not be able to recover their wallet again.
The sign-in details of the cloud account that contains the backup key