You can use "Cold spending" to send Bitcoins from any HD wallet seed.
Ah, that's interesting! I did not know. Thanks. Yes, I found the function!
Cold storage spending from a paper wallet would be much faster and more convenient, but paper wallets have their own problems, related to the insecurity of computers and printers. So this might be a nice solution for secure cold storage, provided the mobile phone with Mycelium is secure.