Envelope budgeting, in the literal sense, means splitting your cash into labelled envelopes — groceries, petrol, entertainment — and when an envelope's empty, that category is done for the month, full stop. It's an old method (people were doing this long before budgeting apps existed) and the reason it still gets recommended is that running out of physical cash is a much harder limit than a number on a screen you can talk yourself past.
You don't need actual envelopes to get that effect. In this tracker, you set a spending limit per category (groceries, eating out, whatever matters to you) and log expenses against it as you go — it's the same "this envelope is empty" signal, just digital, and without needing to carry cash around or make a special trip to top one back up. No bank login either; you add the numbers yourself or import a statement. Just try setting two or three envelopes for next month and see how it changes what you spend on the third one.