If someone has two mobile phones, deciding to use one as a mobile wallet. To me, this is a good idea as one of the phones can be useless. And having in mind to use it as wallet and putting these in consideration.
Having back up of his private keys or seed phrase.
Not using it to go online but online while making transactions
Still install anti malware against malware
So, he use the phone only as wallet and for crypto transactions. So, what do you think. Is this a good idea?
I think it's not a good idea. Why? Almost every smartphones are vulnerable to threats even you install many anti-virus and anti-malware in it. And having your money and private keys stored in just a single device makes it much riskier. If you would only use it for the private key and seed phrase storage, what if you lost it or you accidentally broke it? Better to have backups in a lot of platforms. And, why not use hardware wallets instead?