Sign in

🇭🇰 _Hong Kong App Developer; Android, iOS & Firebase lover; Sharing & Writing can strengthen my knowledges!

IOS allows app to refresh it content even when it is sent to background. iOS can intelligently study the user’s behaviour and schedule background tasks to the moment right before routine usage. It is useful for app to retrieve the latest information from its server and display to user right…


AlarmManager is a bridge between application and Android system alarm service. It can send a broadcast to your app (which can be completely terminated by user) at a scheduled time and your app can then perform any task accordingly.

With the help from PendingIntent and Intent, a bundle of information…


ViewPager2 is introduced in this year 2019 Google I/O and is a replacement of the old ViewPager, which was created in 2011. It includes some new features to enhance UI and coding experience, including:

  1. Right-to-left layout support
  2. Vertical orientation (Scroll vertically)
  3. modifiable Fragment collections


TabLayout is a common widget working with ViewPager and ViewPager2. User can tap on each tap to go to a specific page in ViewPager directly. The most common example is the Google Play Store app.


NFC stands for “Near Field Communication”. Two electronic devices can transmit data through NFC when they are distanced fewer than 4 cm apart. NFC can be used for electronic payment. It was invented many years ago but it has just been introduced by Apple to iPhone series since the launch…


Use Google Map SDK to display a route, Room to save the user’s data, Step counter to get the step count

Cover photo from Unsplash

Running is a healthy habit for all people. It is a great benefit for users to review their running routes and step counts on a map. Android provides a lot of tools for achieving these functions. In this tutorial, you’ll build this kind of tracking app with the following tools:


AVFoundation framework provides lots of functionalities for developers to handle the audio data.

IOS app can access the user’s microphone and encode the audio input. For example, WhatsApp records the user’s voice to send a voice message to others. …


New Presentation Controller with Two Detents

Apple releases a lot of new updates to iOS and Swift programming language in the WWDC 2021. One of the eye-catching UI enhancements is the UISheetPresentationController. It provides a brand new way for presenting an UIViewController . It can be displayed in either half-screen or full-screen mode. …


Sign In With Apple is an authentication system created by Apple. iCloud users can authenticate apps for retrieving their full names and email addresses. Apple provides a proxy email service for users who want to hide their email addresses from app owners who request their email addresses. …

Myrick Chow

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store