Tags / sprite-kit
Here's a simplified version of how you could implement a timer system in your game using Objective-C:
Understanding the SKReferenceNode Issue in iOS 11: A Guide to Resolving Erratic Asset Behavior
Understanding Background Image Sizes in Sprite Kit Games: A Guide to Logical Units and Best Practices
Calling Methods From Your SKScene Class in SpriteKit: A Comprehensive Guide
Understanding View Controller Dismissal and Presentation in iOS: A Solution to Preserving State Between View Controllers