Goodbudget

Goodbudget recreates the envelope method digitally, letting you divvy up a spending pot into categories and watch balances drop as you spend. It syncs across your devices and a partner's or roommate's phone, making it work for shared budgeting.

Since it doesn't plug directly into your bank, you enter transactions manually. The free tier caps you at 20 envelopes, enough for most students but limiting for detailed category tracking.