Do not use the same password that you log-in on your iPhone for anything else.
Do not even do any banking on your iPhone.
Use a separate password to log-in on each bank account when you use your computer to connect to the bank account.
Only do banking with a computer that you have secure with updated security and not on your iPhone. It is also a good thing to check for security updates for your computer and Internet Browser and to clear the download files and cache before logging into accounts.
Backup your iPhone to your computer with encrypted backup with your separate password using iTunes that is different than the one used for your Apple Account or your iPhone. Doing backups onto your computer instead of the Apple Cloud allows you to have all your photos and accounts protected off the cloud and if you lose your iPhone, you will be able to restore your photos and all your data back to your new iPhone via the iTunes backup; that you encrypted with a backup to your local computer. Note: there is a version of iTunes that works on the PC computers, but the Apple iTunes program with iPhoto is what I use for my iPhone and it works good. Note: if you backup to the Cloud, you are playing with too much risk.
In examples of people that have their iPhone stolen, they lost the ability to get anything from the cloud, as the thief changed their password and Apple won’t grant access to you, even though you were the rightful owner of that iPhone at the time you created all you put into the Cloud. Hard lesson to digest when it happens.
No banking on iPhone even though it makes it so nice…and easy for you and the thief.
No Investment accounts on your iPhone.
No backups to the cloud with all your memories…even though Apple says you can get them back if you lose your iPhone. Not true if a thief changes your password to the Cloud and your Apple Account.
No important items of photos on your iPhone such as Social Security number, bank numbers, and on and on.
No tax records recorded on your iPhone.
No photos that compromise your identity, such as Driver’s License, certificates, etc.
If you use a Password Manager, do not use one tied to Apple or Google, but one that is totally separate from all your iPhone and social and mail accounts. Do not allow your password to log into your Password manager to be anything you use to get into your iPhone or Apple or Google or Facebook or other media accounts.
Use complex password that are not words but at least 9 or more characters.