For me, this is the best solution. You will need to still secure your address. So just like what we do every day, you get a certain amount of money from your bank account for your everyday usage.
But people will need to be aware that they will need to change their wallet often atleast may be at every transfer from your large account. Bitcoin is a public ledger. You don't want any people tracking your wallets and its funds right?
Transferring just small amounts to your mobile?
This is what works for me. I have blockchain app installed in my phone. My cold wallet is Ledger neno S. Depending on my expenses, I transfer my BTC from my cold wallet to my blockchain app.
It's like how we do for the fiat money. The concept is, I have money in my bank. When I need money - I take off some money and carry it with me in my wallet.