The use of hot wallets will also be safe if the key or seed phrase consisting of 12-24 words stored in offline storage. CMIIW.
A hot wallet is a wallet that is connected to the internet, so your wallet secrets that is stored locally is prone to hacking because it is exposed to an online enviroment, you may back up your seed phrase on paper and store it safely, but the risk is with your wallet file that is stored in an online device.
AFAIK, if you use a mobile device like an iPhone and only a wallet application is installed without any other applications because your iPhone specializes for a wallet, I think it can provide good security even though the wallet hack can occur beyond your expectations and at any time.
Instead of doing that, it is better to make the device airgapped, in order to be sure that your funds are safe. As long as your wallet is connected to the internet, it is vulnerable to attacks.