A Latin to Cyrillic and Cyrillic to Latin converter (transliterator).
Simple web (online) version using the Serbian alphabet:
More alphabets and features in the Android version. With ~50,000 downloads one of the most successful apps of its kind, while being fully open source! The business logic is available as separate Kotlin Multiplatform library on Maven Central.
Included alphabets in the Android version:
Source Code Android app on GitHub Source Code Kotlin Multiplatform library on GitHub