NO, android apps cannot only be programmed using Java, but it can also be done using C/C++.
To develop an android app using C/C++ you need to use NDK or Native Development Kit. To enable NDK to go to SDK manager and download the following -
- CMAKE
- NDK
- LLDB
By enabling and downloading these you can now write your codes using C/C++.
You can also develop the app using Kotlin, a new language Designed and Developed by JetBrains which makes coding in android much easier. to use Kotlin you need to enable this while you create your new project. Kotlin works on JVM. you need to make sure that you are using android studio 3.0 +.
