Understanding the Issue with Presenting View Controllers Outside of the Window Hierarchy

Background Execution in Response to Push Notifications on iOS: Strategies for Overcoming Apple's Limitations

Retrieving Data from an XML File Stored on a Server Using iPhone App: A Step-by-Step Guide to Downloading and Parsing XML with HTTPS.

Here's a simplified version of how you could implement a timer system in your game using Objective-C:

Detecting iOS Wi-Fi Authentication: Best Practices for Mobile App Development

How to Search for Addresses on an MKMapView Using a UISearchBar with Google Maps' API

Displaying Images from Databases Through Web Services in Collection Views on iOS 5 and Earlier: Solutions and Considerations

Migrating Core Data to Shared App Group for Use in iOS Extensions

Customizing UIAlertView Button Text Fonts in iOS 7: A Step-by-Step Guide

Navigating Between View Controllers in iOS: A Deep Dive