Hello i download Estimote Indoor SDK for Android from github https://github.com/Estimote/Android-Indoor-SDK .
but its in Kotlin is there a version in Java? to download and install in android studio 3
You can use Kotlin and Java interchangeably in your project because they are both byte-code compatible. There is no such thing like Java version or Kotlin version of SDK. Only example app source code is written in Kotlin, probably to encourage users to learn and use this new programming language.