Hard wallet is the best, especially the new ledger where you don’t need to connect your ledger manually. Hackers will have a hard time to hack you, not unless you mistakenly save the details of your wallet on a not safe place. Ledger wallet is the best hard wallet for me, they work smoothly.
There are a number of new hardware wallets all trying to prevent this: online connection. It doesn't get very much secure than that but if you don't practise basic security then you could be vulnerable at other points without even getting to the stage of external hackers. For example, is your device itself compromised from within?
Do you store the keys securely and independently from the wallet? Won't help if you still keep the private key in an email somewhere!
