Minimum Viable Product

...a way to track a budget using a modern electronic device.

Key Features necessary for a minimum viable product:

• The ability to create and manage a basic user account
• The ability for a user to create a budget
• Changes to user accounts, budgets, envelopes, and transactions persist after the app is closed (or the user logs out, etc.)
• The ability to add and remove envelopes from a budget
• The user can both set and change the budget amount for each envelope.
• The user can register transactions (both spending and earning)
• Transactions can be associated with an envelope
• Transactions associated with an envelope change the "remaining balance"