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?
What is the wallet of your friend ? It is sad to hear that the back up is also on that phone. Your friend should also have a copy on his/her laptop or flashdrive or maybe encrypt it into a private account online. Regarding the password, I am not really sure. Maybe yes you can recover it. Just log in the account using the password then try tp explore the wallet if you can get its private key. If you recover it, make sure your friend will transfer the bitcoin into a much safer wallet.