What is difference between Instrument & Deploy App under test?

I would like to know the difference between "Instrument the App under test" and "Deploy the App under test". I'm new in App testing.

The first thing you need to know is that for Ranorex to be able to remotely control an Android App, it has to be instrumented. The instrumentation allows the app to communicate with the Ranorex service (install on the Android device) which in turn communicates with Ranorex test runner (usually through USB). Be aware that instrumenting an app will create a new apk. This new apk is referred as an instrumented version of the apk under test.

The Ranorex instrumentation of an app can be done using the wizard when the option is enabled.

However, sometimes, the instrumentation can be done directly when the app is build on a build server. In this particular case, there is no need to instrument the app before deploying it to a device.

The Deploy option simply installs the app on the device. If for example, you need to deploy your app on many devices, you can instrument it once, then deploy it to many controllers.

You can read about Ranorex instrumentation wizard on Ranorex web site (see Android section): https://www.ranorex.com/help/latest/interfaces-connectivity/instrumentation-wizard/getting-started/

I hope this clarifies things up a little bit.