iOS × App Extensions
iOS App Extensions
We track 9 iOS App Extensions case studies from 8 engineering teams. Carousell, Expo and Kasikornbank write about it most. Many posts also cover UI Performance and UX. The posts run from 2018 to 2025. The newest is from December 2025.
iOS App Extensions articles 1–9 of 9
How to implement iOS widgets in Expo apps
Arthur Spalanzani built an affirmations app where the widget IS the product, not a companion feature. His widget-first approach achieved 80.7% adoption and unlocked organic social sharing that traditional app s...
Integrating Extensions into Large-Scale iOS apps
Lyft's iOS team built an Apple Maps extension that lets users book rides without leaving Maps. But the initial version added 45MB to their app—nearly a quarter of Apple's 200MB cellular download limit.
What's New in the Mobile Payments SDK Beta
Square just launched the successor to their Reader SDK after 6 years, and KIOS was among the first to build with it. Their integration story reveals what's actually possible when payment SDKs are built for deve...
How to Create Dynamic Island and ActivityKit with Flutter
Amorn Apichattanakul from KBTG shows Flutter developers how to tap into iOS's Dynamic Island feature. Yes, you can build Live Activities in Flutter apps—here's the bridge you need.
Tokopedia iOS: Hello 2021, Rewind 2020
Samuel Edwin from Tokopedia reveals how his iOS team achieved a 10x build time reduction while shipping features that got them featured on the App Store. Despite 2020's challenges, they transformed their entire...
Building iOS 14 Widgets for Carousell - Part 2
Jay Ang and Beemo Lee from Carousell's iOS team shipped their first iOS 14 widget in 2020. Their biggest challenge? Two singleton instances fighting each other across app targets.
Building iOS 14 Widgets for Carousell - Part 1
Julia Maurer and Ha Pham from Carousell reveal how they shipped their iOS 14 widget in one sprint. Their secret? Starting with power users who open the app 300 times daily.
Your next upgrade deserves an upgrade
Signal just solved one of iOS's most frustrating problems: losing your encrypted message history when you upgrade devices. imperiopolis walks through how they built a secure, local device-to-device transfer tha...
Building Input Accessory View For React Native
After three years and countless '+1s' on GitHub, React Native finally solved one of iOS development's most requested features. Here's how the team built InputAccessoryView from scratch.