September 6, 2025

Third Edition: How to Build Android Applications with Kotlin

The third edition of our book, How to Build Android Applications with Kotlin, has now been published. It is now fully using Jetpack Compose and had other updates as well.

You’ll learn the fundamentals of app development, enabling you to use Android Studio, as well as get to grips with Jetpack Compose to create your first screens, build apps to run them on virtual devices through guided exercises, and implement Jetpack Compose’s layout groups to make the most of lists, images, and maps. The book has been updated with Kotlin’s powerful networking and coroutines libraries to help you fetch data in the background from a web service and manage displaying the data using Kotlin flows. You’ll learn about testing, creating clean architecture, and persisting data, as well as exploring the dependency injection pattern and learning how to publish your apps on the Google Play Store.

You'll also work on realistic projects split up into bite-size exercises and activities, along with building apps to create quizzes, read news articles, check weather reports, store recipes, retrieve movie information, and remind you where you parked your car.

You can get your copy of the book on Packt and on Amazon.

August 4, 2025

Custom Currency Converter

Travelling to another place with a different currency than yours? Want to know how much the cost exactly is based on the exchange rate used when you bought the new currency or your bank's current rate? Custom Currency Converter is the app for you!

Custom Currency Converter is a currency exchange app that you can use to convert between two currencies using your custom exchange rate. It is my second app that is developed with 100% Jetpack Compose.

You can download the Android app at https://play.google.com/store/apps/details?id=com.tigcal.apps.cent. Let us know what you think of it and your feedback/suggestions.

May 6, 2025

Half Marathon at BMO Vancouver Marathon 2025

After trying the 8k at the BMO Vancouver Marathon 2024, I went back to running a half marathon at the BMO Vancouver Marathon 2025.

I finished the 21.1 km run in 2:11:47, which is a little faster than the last time I ran there (2023). It is a little slower than what I got last year at Vancouver Half Marathon 2024 but comparing the same route means I improve a bit this time.

The record for the run according to the Strava app was 21.62 km in 2:11:48 . It also said I got a few best efforts: Half Marathn (02:08:38) and 20k (2:01:34).


It's good to be back and the postcard with personal results is a great souvenir. I'm hoping I can run again next year.