diff --git a/build.gradle b/build.gradle
index 1b83703bdb7b..e8faf444b7f9 100644
--- a/build.gradle
+++ b/build.gradle
@@ -201,6 +201,8 @@ allprojects {
     }
 }
 
+buildDir "${topobjdir}/gradle/build"
+
 import  org.gradle.api.services.BuildServiceParameters
 abstract class MozconfigService implements BuildService<MozconfigService.Params>, AutoCloseable {
     interface Params extends BuildServiceParameters {
diff --git a/mobile/android/android-components/plugins/config/build.gradle b/mobile/android/android-components/plugins/config/build.gradle
index f1ad8dcd3446..e4302437d731 100644
--- a/mobile/android/android-components/plugins/config/build.gradle
+++ b/mobile/android/android-components/plugins/config/build.gradle
@@ -6,8 +6,6 @@ plugins {
     id "org.gradle.kotlin.kotlin-dsl" version "5.1.2"
 }
 
-buildDir "${gradle.mozconfig.topobjdir}/gradle/build/mobile/android/android-components/plugins/config"
-
 repositories {
     gradle.mozconfig.substs.GRADLE_MAVEN_REPOSITORIES.each { repository ->
         maven {
diff --git a/mobile/android/android-components/plugins/dependencies/build.gradle b/mobile/android/android-components/plugins/dependencies/build.gradle
index 957c42c06d42..c9866094ec44 100644
--- a/mobile/android/android-components/plugins/dependencies/build.gradle
+++ b/mobile/android/android-components/plugins/dependencies/build.gradle
@@ -6,8 +6,6 @@ plugins {
     id "org.gradle.kotlin.kotlin-dsl" version "5.1.2"
 }
 
-buildDir "${gradle.mozconfig.topobjdir}/gradle/build/mobile/android/android-components/plugins/dependencies"
-
 repositories {
         gradle.mozconfig.substs.GRADLE_MAVEN_REPOSITORIES.each { repository ->
             maven {
diff --git a/mobile/android/android-components/plugins/publicsuffixlist/build.gradle b/mobile/android/android-components/plugins/publicsuffixlist/build.gradle
index 65a2fadca09f..3a0f23008a89 100644
--- a/mobile/android/android-components/plugins/publicsuffixlist/build.gradle
+++ b/mobile/android/android-components/plugins/publicsuffixlist/build.gradle
@@ -6,8 +6,6 @@ plugins {
     id "org.gradle.kotlin.kotlin-dsl" version "5.1.2"
 }
 
-buildDir "${gradle.mozconfig.topobjdir}/gradle/build/mobile/android/android-components/plugins/publicsuffixlist"
-
 repositories {
         gradle.mozconfig.substs.GRADLE_MAVEN_REPOSITORIES.each { repository ->
             maven {
diff --git a/mobile/android/android-components/samples/browser/build.gradle b/mobile/android/android-components/samples/browser/build.gradle
index 9d6d8488ab38..af390933ab0a 100644
--- a/mobile/android/android-components/samples/browser/build.gradle
+++ b/mobile/android/android-components/samples/browser/build.gradle
@@ -7,6 +7,10 @@ plugins {
     alias(libs.plugins.kotlin.compose)
 }
 
+if (findProject(":geckoview") != null) {
+    buildDir "${topobjdir}/gradle/build/mobile/android/samples-browser"
+}
+
 apply plugin: 'com.android.application'
 
 android {
diff --git a/mobile/android/annotations/build.gradle b/mobile/android/annotations/build.gradle
index 1afdde715f15..8c1b6685be38 100644
--- a/mobile/android/annotations/build.gradle
+++ b/mobile/android/annotations/build.gradle
@@ -1,3 +1,5 @@
+buildDir "${topobjdir}/gradle/build/mobile/android/annotations"
+
 apply plugin: 'java'
 
 dependencies {
diff --git a/mobile/android/docs/fenix.rst b/mobile/android/docs/fenix.rst
index c687e4bdf70b..b71c23d2d7c9 100644
--- a/mobile/android/docs/fenix.rst
+++ b/mobile/android/docs/fenix.rst
@@ -32,7 +32,7 @@ From the root mozilla-central directory, build Fenix:
     ./mach gradle clean fenix:assembleDebug
 
 You can then find the generated debug apks in objdir under
-``gradle/build/mobile/android/fenix/app/outputs/apk/fenix/debug``
+``gradle/build/mobile/android/fenix/outputs/apk/fenix/debug``
 
 To sign your release builds with your debug key automatically, add the following to `<proj-root>/local.properties`:
 
diff --git a/mobile/android/examples/messaging_example/app/build.gradle b/mobile/android/examples/messaging_example/app/build.gradle
index 999d4751bac1..1a66cced7f26 100644
--- a/mobile/android/examples/messaging_example/app/build.gradle
+++ b/mobile/android/examples/messaging_example/app/build.gradle
@@ -2,6 +2,8 @@ plugins {
     alias(libs.plugins.kotlin.android)
 }
 
+buildDir "${topobjdir}/gradle/build/mobile/android/examples/messaging_example"
+
 apply plugin: 'com.android.application'
 
 android {
diff --git a/mobile/android/examples/port_messaging_example/app/build.gradle b/mobile/android/examples/port_messaging_example/app/build.gradle
index 5d792a5e1e85..b6c5250bee0c 100644
--- a/mobile/android/examples/port_messaging_example/app/build.gradle
+++ b/mobile/android/examples/port_messaging_example/app/build.gradle
@@ -2,6 +2,8 @@ plugins {
     alias(libs.plugins.kotlin.android)
 }
 
+buildDir "${topobjdir}/gradle/build/mobile/android/examples/port_messaging_example"
+
 apply plugin: 'com.android.application'
 
 android {
diff --git a/mobile/android/exoplayer2/build.gradle b/mobile/android/exoplayer2/build.gradle
index e58953297194..8f52dc5d1bc3 100644
--- a/mobile/android/exoplayer2/build.gradle
+++ b/mobile/android/exoplayer2/build.gradle
@@ -1,3 +1,5 @@
+buildDir "${topobjdir}/gradle/build/mobile/android/exoplayer2"
+
 apply plugin: 'com.android.library'
 
 dependencies {
diff --git a/mobile/android/fenix/app/build.gradle b/mobile/android/fenix/app/build.gradle
index 80208ed8e3bd..56d09f45220f 100644
--- a/mobile/android/fenix/app/build.gradle
+++ b/mobile/android/fenix/app/build.gradle
@@ -25,6 +25,10 @@ plugins {
     id "com.google.protobuf" version "$protobuf_plugin"
 }
 
+if (findProject(":geckoview") != null) {
+    buildDir "${topobjdir}/gradle/build/mobile/android/fenix"
+}
+
 apply plugin: 'com.android.application'
 apply plugin: 'kotlin-parcelize'
 apply plugin: 'jacoco'
diff --git a/mobile/android/fenix/plugins/apksize/build.gradle b/mobile/android/fenix/plugins/apksize/build.gradle
index 04ed51f995d5..f253620622bb 100644
--- a/mobile/android/fenix/plugins/apksize/build.gradle
+++ b/mobile/android/fenix/plugins/apksize/build.gradle
@@ -6,8 +6,6 @@ plugins {
     id "org.gradle.kotlin.kotlin-dsl" version "5.1.2"
 }
 
-buildDir "${gradle.mozconfig.topobjdir}/gradle/build/mobile/android/fenix/plugins/apksize"
-
 repositories {
         gradle.mozconfig.substs.GRADLE_MAVEN_REPOSITORIES.each { repository ->
             maven {
diff --git a/mobile/android/focus-android/app/build.gradle b/mobile/android/focus-android/app/build.gradle
index 45facba394db..a9b971db360f 100644
--- a/mobile/android/focus-android/app/build.gradle
+++ b/mobile/android/focus-android/app/build.gradle
@@ -4,6 +4,10 @@ plugins {
     id "com.jetbrains.python.envs" version "$python_envs_plugin"
 }
 
+if (findProject(":geckoview") != null) {
+    buildDir "${topobjdir}/gradle/build/mobile/android/focus-android"
+}
+
 apply plugin: 'com.android.application'
 apply plugin: 'kotlin-parcelize'
 apply plugin: 'jacoco'
diff --git a/mobile/android/geckoview/build.gradle b/mobile/android/geckoview/build.gradle
index e73c4df96b22..a36de64443e2 100644
--- a/mobile/android/geckoview/build.gradle
+++ b/mobile/android/geckoview/build.gradle
@@ -2,6 +2,8 @@ plugins {
     alias(libs.plugins.kotlin.android)
 }
 
+buildDir "${topobjdir}/gradle/build/mobile/android/geckoview"
+
 import groovy.json.JsonOutput
 
 apply plugin: 'com.android.library'
diff --git a/mobile/android/geckoview_example/build.gradle b/mobile/android/geckoview_example/build.gradle
index dd372ddefb3f..9b0549404720 100644
--- a/mobile/android/geckoview_example/build.gradle
+++ b/mobile/android/geckoview_example/build.gradle
@@ -2,6 +2,8 @@ plugins {
     alias(libs.plugins.kotlin.android)
 }
 
+buildDir "${topobjdir}/gradle/build/mobile/android/geckoview_example"
+
 apply plugin: 'com.android.application'
 
 android {
diff --git a/mobile/android/shared-settings.gradle b/mobile/android/shared-settings.gradle
index 8115c320140f..442f3039b677 100644
--- a/mobile/android/shared-settings.gradle
+++ b/mobile/android/shared-settings.gradle
@@ -177,29 +177,4 @@ gradle.projectsLoaded { ->
             }
         }
     }
-
-    // If we are doing a top-level build, initialize all project buildDirs to be
-    // in ${topobjdir} to follow conventions of mozilla-central build system.
-    // Specific subproject builds like fenix continue to build in source tree to
-    // avoiding breaking existing automation.
-    if (findProject(":geckoview") != null) {
-        gradle.rootProject.allprojects { project ->
-            def topSrcPath = file(gradle.mozconfig.topsrcdir).toPath()
-            def topObjPath = file(gradle.mozconfig.topobjdir).toPath()
-
-            def sourcePath = project.getBuildFile().toPath().getParent()
-            def relativePath = topSrcPath.relativize(sourcePath)
-
-            if (relativePath.startsWith("..")) {
-                // The project doesn't appear to be in topsrcdir so leave the
-                // buildDir alone.
-            } else {
-                // Transplant the project path into "${topobjdir}/gradle/build".
-                // This is consistent with existing gradle / taskcluster
-                // configurations but less consistent with the result of the
-                // non-gradle build system.
-                buildDir topObjPath.resolve("gradle/build").resolve(relativePath)
-            }
-        }
-    }
 }
diff --git a/mobile/android/test_runner/build.gradle b/mobile/android/test_runner/build.gradle
index b78e8e8d90ca..4cb589a7d162 100644
--- a/mobile/android/test_runner/build.gradle
+++ b/mobile/android/test_runner/build.gradle
@@ -2,6 +2,8 @@ plugins {
     alias(libs.plugins.kotlin.android)
 }
 
+buildDir "${topobjdir}/gradle/build/mobile/android/test_runner"
+
 apply plugin: 'com.android.application'
 
 android {
diff --git a/taskcluster/kinds/build/fenix.yml b/taskcluster/kinds/build/fenix.yml
index b1885f78f07e..e987d5bbc636 100644
--- a/taskcluster/kinds/build/fenix.yml
+++ b/taskcluster/kinds/build/fenix.yml
@@ -50,7 +50,7 @@ android-aarch64-fenix/debug:
             TOOLTOOL_MANIFEST: "mobile/android/config/tooltool-manifests/android/releng.manifest"
         artifacts:
             - name: public/build/fenix.apk
-              path: /builds/worker/workspace/obj-build/gradle/build/mobile/android/fenix/app/outputs/apk/fenix/debug/fenix-fenix-arm64-v8a-debug.apk
+              path: /builds/worker/workspace/obj-build/gradle/build/mobile/android/fenix/outputs/apk/fenix/debug/fenix-fenix-x86-debug.apk
               type: file
     run:
         custom-build-variant-cfg: aarch64-fenix-debug