Can C++/Qt be used to create apps for Android devices?

I have use Eclipse SDK (Java) to mostly create Android apps but yes I can confirm you can also program part of your Android apps using C++ but the benefits are limited.  Here is the NDK:

"Android NDK

The NDK is a toolset that allows you to implement parts of your app using native-code languages such as C and C++. Typically, good use cases for the NDK are CPU-intensive applications such as game engines, signal processing, and physics simulation.

Before downloading the NDK, you should understand that the NDK will not benefit most apps. As a developer, you need to balance its benefits against its drawbacks. Notably, using native code on Android generally does not result in a noticable performance improvement, but it always increases your app complexity. In general, you should only use the NDK if it is essential to your app—never because you simply prefer to program in C/C++. When examining whether or not you should develop in native code, think about your requirements and see if the Android framework APIs provide the functionality that you need."

http://developer.android.com/tools/sdk/ndk/index.html

part of your Android apps using C++

So C++ can only be "part" of an Android app? You can't write an Android app entirely in C++ and do away with Java?

Thank you for your response, it was very insightful to me.

Glad to help.  Cheers!