I started using my bank's app specifically due to long trips. With the app there is no issue regarding location when logging in. My bank requires 2-factor authentication when I login via web browser but it does not with the app so the VPN wouldn't be necessary. (I am assuming you will have ship wifi)
I also have all my regular bills sent to email notifications so I get the information to pay the water, electric bill, etc. Of course, you could set these payments in advance with a bit extra to ensure you've fully covered the payment.
Finally, I also set up the app for my travel credit cards so that I can easily monitor them.