App getting crashed in version 5.0

Question

The problem I am facing is that my android application works well on devices 4.4.2 and below, but crashes on devices having Lollipop(5.0) and its corresponding higher versions.I know that its somehow related to the build tools in my gradle file,but still not able to figure out the problem.Could someone please help me out with this.

This is my gradle file,

apply plugin: 'com.android.application'

android {


    compileSdkVersion 23
    buildToolsVersion '23.0.1'

    defaultConfig {
        applicationId "com.vs.vertosys"
        minSdkVersion 14
        targetSdkVersion 23
        multiDexEnabled true
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}
repositories {
    jcenter() {}

}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.1.1'
    compile 'com.android.support:support-v4:23.1.1'
    compile 'com.android.support:multidex:1.0.1'
    // compile 'com.android.support:appcompat-v4:23.1.1'
    compile 'com.google.android.gms:play-services-gcm:8.4.0'
    compile 'com.google.android.gms:play-services-location:+'
    compile 'com.pushwoosh:pushwoosh:+'
}