I think bitcoin will not replace the bank because Bitcoin is the first non-centralized digital currency,Like money in general, Bitcoin can be used to store wealth and to purchase goods electronically,While banks regulate the circulation of money such as the euro and the dollar..
But all the things the bank can do can also done by Bitcoin. We only need to wait until bitcoin is recognized as the bank being recognize. I do think that bitcoin will replace banks in the future. There will be a digital bank to store all our money and currencies.