Not sure if anyone has similar experience, but today my mum's phone was hacked where her Whatsapp was black-out. The hacker started sending messages to her contacts asking for money. He even provided a bank account number (Bank Islam), although the name is obviously fake. He also managed to transfer out money from Touch N Go, but bank-related transfers are safe. During this period, my mum's phone was not usable.

A police report has been made although I don't expect much hope to recover the money. Just sharing in case anyone knows what could have caused this.

Side note, is iOS more secure when it comes to hacking?

Do you mean it's a standard practice to have 2 phones, one specifically for banking?
What about E-wallet? Doesnt sound practical to separate this

A 2-year old Vivo phone. How is that different from other Android phone like Samsung, Google, etc?

One thing I don't understand is how can the scammer transfer money out from Touch N Go? Unless he already know the password

Means if you go out to buy stuff that will need E-wallet, you will have to bring both phones too?