Instrumentation Tests with usage of Spoon setup error

I am trying to run my tests with usage of Spoon.

According to setup guide I found there: http://ift.tt/1wZcMiF , I've set few simple changes to my project.

First: I've added dependency in my root build.gradle file:

buildscript {
    repositories {
        jcenter()
        mavenCentral()
        (...)
    }
    dependencies {
        (...)
        classpath 'com.stanfy.spoon:spoon-gradle-plugin:1.0.2'
    }
}

allprojects {
    repositories {
        jcenter()
        mavenCentral()
    }
}

Second: in my app package build.gradle I've added:

apply plugin: 'spoon'

And dependency:

androidTestCompile 'com.squareup.spoon:spoon-client:1.1.9'

And specified that I want to use debug builds:

spoon {
    debug true
}

Third: I go to terminal, set directory to my project root and invoke

./gradlew spoon

I receive this output and error. What may be causing this?

2015-10-20 17:28:12 [SR.runTests] Executing instrumentation suite on 1 device(s).
2015-10-20 17:28:12 [SR.runTests] Application: com.azimo.sendmoney.debug1 from /Users/F1sherKK/Dev/Azimo-Android/app/build/outputs/apk/app-debug.apk
2015-10-20 17:28:12 [SR.runTests] Instrumentation: com.azimo.sendmoney.debug1.test from /Users/F1sherKK/Dev/Azimo-Android/app/build/outputs/apk/app-debug-androidTest-unaligned.apk
2015-10-20 17:28:12 [SR.runTests] [1903cdc7] Starting execution.
2015-10-20 17:28:12 [SDR.run] InstrumentationInfo: [com.squareup.spoon.SpoonInstrumentationInfo@7baf516e[applicationPackage=com.azimo.sendmoney.debug1,instrumentationPackage=com.azimo.sendmoney.debug1.test,testRunnerClass=android.support.test.runner.AndroidJUnitRunner]]
2015-10-20 17:28:12 [SDR.run] Got realDevice for [1903cdc7]
2015-10-20 17:28:12 [SDR.run] [1903cdc7] setDeviceDetails com.squareup.spoon.DeviceDetails@22444900[model=GT-I9505,manufacturer=samsung,version=5.0.1,apiLevel=21,language=en,region=GB,isEmulator=false,avdName=<null>]
2015-10-20 17:28:12 [SR.runTests] [1903cdc7] Execution done.
:app:spoonDebugAndroidTest FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:spoonDebugAndroidTest'.
> com.android.ddmlib.IDevice.installPackage(Ljava/lang/String;Z[Ljava/lang/String;)Ljava/lang/String;