I dont get the point...
Where does the key come from?
If I generated a new address, how am I supposed to be able to immediately send from it?
There is nothing on it... and until I received funds there, every app will have had plenty of time to persist the key, wont it?
If I scanned the key, well, i have a persistent copy already.
Is your concern something like:
I generate address, hand it to someone, then some crash occurs, I dont have the priv key, but receive money on the address?
Really, as well as the key being trapped in some buffer, your smartphone could catch fire or whatever.
Just use keys with a backup
Where does the key come from?
If I generated a new address, how am I supposed to be able to immediately send from it?
There is nothing on it... and until I received funds there, every app will have had plenty of time to persist the key, wont it?
If I scanned the key, well, i have a persistent copy already.
Is your concern something like:
I generate address, hand it to someone, then some crash occurs, I dont have the priv key, but receive money on the address?
Really, as well as the key being trapped in some buffer, your smartphone could catch fire or whatever.
Just use keys with a backup
That's the point. If I have a wallet software which does predictable syncing of private keys prior to their usage, it can be plugged to a filesystem abstraction offering additional security like redundant storage (thereby handling your flaming smartphone concern).
Secure software isn't normally designed using the "we don't need security because things could catch fire" paradigm.