Update free-courses-id.md (#3773)

free-courses-id.md

 ### Index
 
+* [Android](#android)
+* [Dart](#dart)
+* [Flutter](#flutter)
 * [Go](#go)
 * [HTML / CSS](#html--css)
 * [Java](#java)
@@ -9,9 +12,26 @@
 * [Python](#python)
 
 
+### Android
+
+* [Tutorial Android (Java)](https://www.youtube.com/playlist?list=PLKPnl-eD7EA4rAzNeXikfCq5yiMuFI1zo) - Kopianan
+* [Tutorial Android (Kotlin)](https://www.youtube.com/playlist?list=PLaoF-xhnnrRUEbF6cvk4-CeBAEOSbp8sS) - EDMT Dev
+
+
+### Dart
+
+* [Pemrograman Berorientasi Objek - Dart](https://www.youtube.com/playlist?list=PLZS-MHyEIRo7cgStrKAMhgnOT66z2qKz1) - Erico Darmawan Handoyo
+
+
+### Flutter
+
+* [Flutter Tutorial (Flutter Fundamentals)](https://www.youtube.com/playlist?list=PLZQbl9Jhl-VACm40h5t6QMDB92WlopQmV) - Erico Darmawan Handoyo
+
+
 ### Go
 
 * [Belajar Go-Lang untuk Pemula](https://www.youtube.com/playlist?list=PL-CtdCApEFH_t5_dtCQZgWJqWF45WRgZw) - Programmer Zaman Now
+* [Belajar Golang Basic Bahasa Indonesia](https://www.youtube.com/playlist?list=PLCZlgfAG0GXDztO-BFc9R5afhP26Dhsgm) - Sekolah Koding
 
 
 ### HTML / CSS