diff --git a/Device-Tests-&-Coverage-Report.md b/Device-Tests-&-Coverage-Report.md
index b20463d..b6a35ba 100644
--- a/Device-Tests-&-Coverage-Report.md
+++ b/Device-Tests-&-Coverage-Report.md
@@ -53,10 +53,16 @@ Enable ``apply from: 'coverage.gradle'`` in ``usbSerialForAndroid/build.gradle``
 
 Remove previous test results with ``gradle clean`` or *Android Studio : Menu -> Build -> Clean Project*
 
-For each **device** *flavor* defined in ``coverage.gradle`` execute the corresponding gradle task  
+## Run unit tests
+Disable ``testCoverageEnabled true`` and execute gradle task *usb-serial-for-android -> usbSerialForAndroid -> verification -> testAnyDeviceDebugTest*.
+
+Note: with enabled ``testCoverageEnabled true`` the test fails or creates an empty __*.exec__ report file. You can check this by loading *usbSerialForAndroid/build/jacoco/testAnyDeviceDebugUnitTest.exec* with *Android Studio -> Run -> Show Code Coverage Data*.
+
+## Run device tests
+Enable ``testCoverageEnabled true`` and for each **device** *flavor* defined in ``coverage.gradle`` execute the corresponding gradle task  
 *usb-serial-for-android -> usbSerialForAndroid -> verification -> create***Device***DebugCoverageReport* or  
 *usb-serial-for-android -> usbSerialForAndroid -> other -> create***Device***DebugAndroidTestCoverageReport*.  
-Both tasks create the required *.ec report files but html reports do not contain annotated source code.
+Both tasks create the required __*.ec__ report files but html reports do not contain annotated source code.
 
 Test reports are created even if tests fail. Nevertheless you should check that it didn't fail completely.