CodePath-iOS-TipCalculator

Pre-work assignment: Build a tip calculator using swift to practice iOS mobile development.

User Story:

The following required functionality is complete:

• User can enter a bill amount.
• User can choose a tip percentage.
• User can see the combined total (tip plus bill amount).
• User can change the tip percentage and the total will also change.

The following optional features are implemented:

• Enable Navigation between Screens
• Remembering the bill amount across app restarts (if <10mins)
• Using locale-specific currency and currency thousands separators.
• Making sure the keyboard is always visible and the bill amount is always the first responder.

Note: keyboard does not always appear though .becomeFirstResponder() is implemented on line 35 of the ViewController