Android

 1. belajar intent klik tombol lari ke halaman berikut nya 

https://www.twoh.co/2018/05/13/belajar-memahami-konsep-activity-dan-intent-dengan-kotlin-di-android/

2. btc tracker  kotlin

https://medium.com/swlh/android-tutorial-part-1-using-java-websocket-with-kotlin-646a5f1f09de

3. insert sqlite 

https://www.javatpoint.com/kotlin-android-sqlite-tutorial#