Understanding the aspects of iOS App Launch Time | by Ravi Aggarwal | Medium

First impressions matter. For iOS apps, that means every millisecond between tap and first screen counts.

Ravi Aggarwal breaks down the anatomy of iOS app launch time, explaining why this metric matters when users launch apps multiple times daily. He covers the technical phases that determine whether your app feels fast or frustrating.

Key Takeaways

• Cold launches take longest: app process doesn't exist in kernel cache yet
• Pre-main() time: kernel loads your Mach-O executable before code runs
• Warm and hot launches reuse existing process data from system memory
• Launch time spans from icon tap to first view drawn on screen

The article dives into specific optimization techniques for each launch phase that can dramatically reduce perceived wait times.