TipCalc: A tip calculator app

Project 1 of CodePath Android Bootcamp.
Time to complete: 5 hours

Completed stories
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Required:
 User is displayed the tip of specified percentage for specified entered amount
 User enters the total amount of the transaction
 User can select between tip amounts (i.e 10%, 15%, 20%)
 Upon selecting tip amount, formatted tip value is displayed

Optional:
 User changes the total amount and updated tip is reflected automatically
 User can select how many ways to split the tip
 User can select custom tip percentage if desired
 User can edit preset tip percentages and have them persist across launches
 Experiment with trying input widgets to replace the buttons and/or textviews

Note: No currency symbols are shown in the app. This is intentional, as tip
calculation is independent of the currency being used.

See TipCalcDemo.gif for a demo recording of the app in use.