Unable to see my App

Hi,

I've had some strange issues to get past but I have been able to build my "Hello World" app. I followed the instructions found here: h t t p s:// developer. android. com/ training/ basics/ firstapp/ index.html

So now I have it built, I run the emulator and I cannot see my app. I try using my phone and same thing, I cannot see my app.

I downloaded a sample app, built that and I can see the app in my emulator (and phone) after I turn off my anti-virus software.

So here are the issues I have resolved to get my "Hello World" app to compile/build:
1. When I created the new project and first built it I had errors relating to the colors.xml and dimens.xml files not being complete, therefore the xml was invalid. I searched the internet and found examples of these files so corrected them. I have confirmed that the color and dimen names are the only ones referred to.
2. The next issue was invalid *.png files. I was able to work out which files they were and copied a valid png file and renamed it to replace the invalid files.

Here is my Gradle Console, post build:
Executing tasks: [clean, :app:generateDebugSources, :app:generateDebugAndroidTestSources, :app:mockableAndroidJar, :app:prepareDebugUnitTestDependencies, :app:compileDebugSources, :app:compileDebugAndroidTestSources, :app:compileDebugUnitTestSources]

Configuration on demand is an incubating feature.
Incremental java compilation is an incubating feature.
:clean
:app:clean
:app:preBuild UP-TO-DATE
:app:preDebugBuild UP-TO-DATE
:app:checkDebugManifest
:app:preReleaseBuild UP-TO-DATE
:app:prepareComAndroidSupportAnimatedVectorDrawable2421Library
:app:prepareComAndroidSupportAppcompatV72421Library
:app:prepareComAndroidSupportSupportCompat2421Library
:app:prepareComAndroidSupportSupportCoreUi2421Library
:app:prepareComAndroidSupportSupportCoreUtils2421Library
:app:prepareComAndroidSupportSupportFragment2421Library
:app:prepareComAndroidSupportSupportMediaCompat2421Library
:app:prepareComAndroidSupportSupportV42421Library
:app:prepareComAndroidSupportSupportVectorDrawable2421Library
:app:prepareDebugDependencies
:app:compileDebugAidl
:app:compileDebugRenderscript
:app:generateDebugBuildConfig
:app:mergeDebugShaders
:app:compileDebugShaders
:app:generateDebugAssets
:app:mergeDebugAssets
:app:generateDebugResValues UP-TO-DATE
:app:generateDebugResources
:app:mergeDebugResources
:app:processDebugManifest
:app:processDebugResources
:app:generateDebugSources
:app:preDebugAndroidTestBuild UP-TO-DATE
:app:prepareDebugAndroidTestDependencies
:app:compileDebugAndroidTestAidl
:app:processDebugAndroidTestManifest
:app:compileDebugAndroidTestRenderscript
:app:generateDebugAndroidTestBuildConfig
:app:mergeDebugAndroidTestShaders
:app:compileDebugAndroidTestShaders
:app:generateDebugAndroidTestAssets
:app:mergeDebugAndroidTestAssets
:app:generateDebugAndroidTestResValues UP-TO-DATE
:app:generateDebugAndroidTestResources
:app:mergeDebugAndroidTestResources
:app:processDebugAndroidTestResources
:app:generateDebugAndroidTestSources
:app:mockableAndroidJar
:app:preDebugUnitTestBuild UP-TO-DATE
:app:prepareDebugUnitTestDependencies
:app:incrementalDebugJavaCompilationSafeguard
:app:compileDebugJavaWithJavac
:app:compileDebugJavaWithJavac - is not incremental (e.g. outputs have changed, no previous execution, etc.).
:app:compileDebugNdk UP-TO-DATE
:app:compileDebugSources
:app:incrementalDebugAndroidTestJavaCompilationSafeguard
:app:compileDebugAndroidTestJavaWithJavac
:app:compileDebugAndroidTestJavaWithJavac - is not incremental (e.g. outputs have changed, no previous execution, etc.).

Note: C:\Users\Peter\APPs\Test_20161002\app\src\androidTest\java\com\example\test_20161002\ApplicationTest.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.

:app:compileDebugAndroidTestNdk UP-TO-DATE
:app:compileDebugAndroidTestSources
:app:incrementalDebugUnitTestJavaCompilationSafeguard UP-TO-DATE
:app:compileDebugUnitTestJavaWithJavac
:app:compileDebugUnitTestJavaWithJavac - is not incremental (e.g. outputs have changed, no previous execution, etc.).
:app:processDebugJavaRes UP-TO-DATE
:app:processDebugUnitTestJavaRes UP-TO-DATE
:app:compileDebugUnitTestSources

BUILD SUCCESSFUL

Total time: 4 mins 33.501 secs

Can you please help me here as I cannot understand why I cannot view my app, and obviously cannot go any further on my quest to become an app developer.

Thanks
Pete

Resolved; it was a version of the emulator issue. Used earliest possible, ie. API 9 and yes it works. And I guess not compatible with my newish phone.

Thanks