As a User, I can play with iPhone

## As a User, I can play with iPhone

### Acceptance Criteria
1. Uses native pixels on retina display devices for better performance (viewport hack)
1. Shows on-screen arrow and action button controls for touch movement and action performing

### Tasks
1. Add viewport hack for Retina display devices
1. Revert viewport hack if Retina display is not detected
1. Add on-screen controls for touch devices

### Additional Notes
- None

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