How do you handle partnership accounts and expenses?

I am launching a new business with a partner. We'd like to set up a shared account where we can both contribute an initial set of funds to use for startup expenses. I know we could go to the bank and set up a business account, but that seems so old school. I've used PayPal to take payments on my website, but not sure about setting up another business account to keep this new venture separate. Do any of you use PayPal, Stripe, Venmo or something else for this purpose? I'd love to hear pro's and con's of your experiences and what folks suggest. Thanks!