They wrote about this a while ago, why they chose the methods they did. My kids both use Muun. They've both recovered their wallets themselves with ease, multiple times, when they get new phones.
Discussion
thoughts on Muun transactions being fake lightning transactions?
I wish they explained better how it works. That said, for me Muun's model is better than Wallet of Satoshi.
how come?
Muun is non-custodial, Wallet of Satoshi is not.
what are your thoughts on Muun not using *real* lightning transactions?
Obviously they _are_ real lightning payments, otherwise they wouldn't work with other wallets. It's just that Muun is an on-chain wallet so it uses Muun's server to send and receive lightning payments. I don't really mind this, I just hope they were more transparent about it. Also I don't think this model will scale well in the long term.
Can you point to any documentation/articles that describe how Muun accomplishes it's submarine swap? Or do they keep it proprietary?