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The design also includes "+" and "-" icons for users to quickly add multiple categories, income, expenses, or email addresses to share a budget with. This greatly increases efficiency - if a user waits until the end of the week to input all accumulated receipts, he would not have to input each item individually and have to navigate back to the same screen multiple times. This feature is very intuitive and thus learnable as well. In addition, the "-" icons make it easy for a user to recover from the error of adding an extra category, expense, or email, although accidentally deleting an item is not quite as recoverable.
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