A friend of mine had some Bitcoin on his phone a couple of years ago and he's lost that phone which stored the private keys on without any other backup. We can see his balance on the blockchain and he knows his password for the private keys. Is there a way of creating the private key from the bitcoin address and the known password?
You can create a new password but you cannot change your private keys. You must know where to put your private keys in the right place and I think our phone is not a good storage for private keys. I think it is better to put your private keys in your email, as long as you can handle to manage your email and to save it or maybe if you have a Dropbox account.