diff --git a/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetAppPlayStoreUrlUseCaseTest.java b/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetAppPlayStoreUrlUseCaseTest.java
index 10dd81db..d54474f2 100644
--- a/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetAppPlayStoreUrlUseCaseTest.java
+++ b/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetAppPlayStoreUrlUseCaseTest.java
@@ -1,7 +1,6 @@
 package com.d4rk.androidtutorials.java.domain.home;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
@@ -9,53 +8,48 @@
 
 import com.d4rk.androidtutorials.java.data.repository.HomeRepository;
 
+import org.junit.Before;
 import org.junit.Test;
 
 public class GetAppPlayStoreUrlUseCaseTest {
 
-    @Test
-    public void invokeReturnsAppUrl() {
-        HomeRepository repository = mock(HomeRepository.class);
-        when(repository.getAppPlayStoreUrl("pkg")).thenReturn("url");
-        GetAppPlayStoreUrlUseCase useCase = new GetAppPlayStoreUrlUseCase(repository);
+    private static final String PACKAGE_NAME = "com.example.pkg";
 
-        String result = useCase.invoke("pkg");
+    private HomeRepository repository;
+    private GetAppPlayStoreUrlUseCase useCase;
 
-        assertEquals("url", result);
-        verify(repository).getAppPlayStoreUrl("pkg");
+    @Before
+    public void setUp() {
+        repository = mock(HomeRepository.class);
+        useCase = new GetAppPlayStoreUrlUseCase(repository);
     }
 
     @Test
-    public void invokeDelegatesNullPackageName() {
-        HomeRepository repository = mock(HomeRepository.class);
-        when(repository.getAppPlayStoreUrl(null)).thenReturn("fallback");
-        GetAppPlayStoreUrlUseCase useCase = new GetAppPlayStoreUrlUseCase(repository);
+    public void invokeReturnsUrlForPackage() {
+        when(repository.getAppPlayStoreUrl(PACKAGE_NAME)).thenReturn("https://play.store/app/com.example.pkg");
 
-        String result = useCase.invoke(null);
+        String result = useCase.invoke(PACKAGE_NAME);
 
-        assertEquals("fallback", result);
-        verify(repository).getAppPlayStoreUrl(null);
+        assertEquals("https://play.store/app/com.example.pkg", result);
+        verify(repository).getAppPlayStoreUrl(PACKAGE_NAME);
     }
 
     @Test
-    public void invokeReturnsNullWhenRepositoryReturnsNull() {
-        HomeRepository repository = mock(HomeRepository.class);
-        when(repository.getAppPlayStoreUrl("pkg")).thenReturn(null);
-        GetAppPlayStoreUrlUseCase useCase = new GetAppPlayStoreUrlUseCase(repository);
+    public void invokeReturnsEmptyUrlWhenRepositoryReturnsEmpty() {
+        when(repository.getAppPlayStoreUrl(PACKAGE_NAME)).thenReturn("");
 
-        String result = useCase.invoke("pkg");
+        String result = useCase.invoke(PACKAGE_NAME);
 
-        assertNull(result);
-        verify(repository).getAppPlayStoreUrl("pkg");
+        assertEquals("", result);
+        verify(repository).getAppPlayStoreUrl(PACKAGE_NAME);
     }
 
     @Test
     public void invokePropagatesRepositoryException() {
-        HomeRepository repository = mock(HomeRepository.class);
-        when(repository.getAppPlayStoreUrl("pkg")).thenThrow(new IllegalStateException("err"));
-        GetAppPlayStoreUrlUseCase useCase = new GetAppPlayStoreUrlUseCase(repository);
+        when(repository.getAppPlayStoreUrl(PACKAGE_NAME))
+                .thenThrow(new IllegalArgumentException("invalid package"));
 
-        assertThrows(IllegalStateException.class, () -> useCase.invoke("pkg"));
-        verify(repository).getAppPlayStoreUrl("pkg");
+        assertThrows(IllegalArgumentException.class, () -> useCase.invoke(PACKAGE_NAME));
+        verify(repository).getAppPlayStoreUrl(PACKAGE_NAME);
     }
 }
diff --git a/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetDailyTipUseCaseTest.java b/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetDailyTipUseCaseTest.java
index 63adaee6..fde253ee 100644
--- a/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetDailyTipUseCaseTest.java
+++ b/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetDailyTipUseCaseTest.java
@@ -8,27 +8,33 @@
 
 import com.d4rk.androidtutorials.java.data.repository.HomeRepository;
 
+import org.junit.Before;
 import org.junit.Test;
 
 public class GetDailyTipUseCaseTest {
 
+    private HomeRepository repository;
+    private GetDailyTipUseCase useCase;
+
+    @Before
+    public void setUp() {
+        repository = mock(HomeRepository.class);
+        useCase = new GetDailyTipUseCase(repository);
+    }
+
     @Test
-    public void invokeReturnsDailyTip() {
-        HomeRepository repository = mock(HomeRepository.class);
-        when(repository.dailyTip()).thenReturn("tip");
-        GetDailyTipUseCase useCase = new GetDailyTipUseCase(repository);
+    public void invokeReturnsRepositoryTip() {
+        when(repository.dailyTip()).thenReturn("Tip of the day");
 
         String result = useCase.invoke();
 
-        assertEquals("tip", result);
+        assertEquals("Tip of the day", result);
         verify(repository).dailyTip();
     }
 
     @Test
-    public void invokeHandlesEmptyTip() {
-        HomeRepository repository = mock(HomeRepository.class);
+    public void invokeReturnsEmptyTip() {
         when(repository.dailyTip()).thenReturn("");
-        GetDailyTipUseCase useCase = new GetDailyTipUseCase(repository);
 
         String result = useCase.invoke();
 
@@ -38,11 +44,9 @@ public void invokeHandlesEmptyTip() {
 
     @Test
     public void invokePropagatesRepositoryException() {
-        HomeRepository repository = mock(HomeRepository.class);
-        when(repository.dailyTip()).thenThrow(new IllegalArgumentException("bad"));
-        GetDailyTipUseCase useCase = new GetDailyTipUseCase(repository);
+        when(repository.dailyTip()).thenThrow(new IllegalStateException("not available"));
 
-        assertThrows(IllegalArgumentException.class, useCase::invoke);
+        assertThrows(IllegalStateException.class, useCase::invoke);
         verify(repository).dailyTip();
     }
 }
diff --git a/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetPlayStoreUrlUseCaseTest.java b/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetPlayStoreUrlUseCaseTest.java
index e3f2aca1..e82131a0 100644
--- a/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetPlayStoreUrlUseCaseTest.java
+++ b/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetPlayStoreUrlUseCaseTest.java
@@ -1,7 +1,6 @@
 package com.d4rk.androidtutorials.java.domain.home;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
@@ -9,41 +8,45 @@
 
 import com.d4rk.androidtutorials.java.data.repository.HomeRepository;
 
+import org.junit.Before;
 import org.junit.Test;
 
 public class GetPlayStoreUrlUseCaseTest {
 
+    private HomeRepository repository;
+    private GetPlayStoreUrlUseCase useCase;
+
+    @Before
+    public void setUp() {
+        repository = mock(HomeRepository.class);
+        useCase = new GetPlayStoreUrlUseCase(repository);
+    }
+
     @Test
-    public void invokeReturnsUrl() {
-        HomeRepository repository = mock(HomeRepository.class);
-        when(repository.getPlayStoreUrl()).thenReturn("url");
-        GetPlayStoreUrlUseCase useCase = new GetPlayStoreUrlUseCase(repository);
+    public void invokeReturnsRepositoryUrl() {
+        when(repository.getPlayStoreUrl()).thenReturn("https://play.store/app");
 
         String result = useCase.invoke();
 
-        assertEquals("url", result);
+        assertEquals("https://play.store/app", result);
         verify(repository).getPlayStoreUrl();
     }
 
     @Test
-    public void invokeReturnsNullWhenRepositoryReturnsNull() {
-        HomeRepository repository = mock(HomeRepository.class);
-        when(repository.getPlayStoreUrl()).thenReturn(null);
-        GetPlayStoreUrlUseCase useCase = new GetPlayStoreUrlUseCase(repository);
+    public void invokeReturnsEmptyUrlWhenRepositoryReturnsEmpty() {
+        when(repository.getPlayStoreUrl()).thenReturn("");
 
         String result = useCase.invoke();
 
-        assertNull(result);
+        assertEquals("", result);
         verify(repository).getPlayStoreUrl();
     }
 
     @Test
     public void invokePropagatesRepositoryException() {
-        HomeRepository repository = mock(HomeRepository.class);
-        when(repository.getPlayStoreUrl()).thenThrow(new RuntimeException("fail"));
-        GetPlayStoreUrlUseCase useCase = new GetPlayStoreUrlUseCase(repository);
+        when(repository.getPlayStoreUrl()).thenThrow(new IllegalStateException("missing"));
 
-        assertThrows(RuntimeException.class, useCase::invoke);
+        assertThrows(IllegalStateException.class, useCase::invoke);
         verify(repository).getPlayStoreUrl();
     }
 }
diff --git a/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetPromotedAppsUseCaseTest.java b/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetPromotedAppsUseCaseTest.java
index 271a1627..65fcd8c4 100644
--- a/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetPromotedAppsUseCaseTest.java
+++ b/app/src/test/java/com/d4rk/androidtutorials/java/domain/home/GetPromotedAppsUseCaseTest.java
@@ -1,7 +1,7 @@
 package com.d4rk.androidtutorials.java.domain.home;
 
 import static org.junit.Assert.assertThrows;
-import static org.mockito.Mockito.any;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
@@ -9,6 +9,7 @@
 import com.d4rk.androidtutorials.java.data.model.PromotedApp;
 import com.d4rk.androidtutorials.java.data.repository.HomeRepository;
 
+import org.junit.Before;
 import org.junit.Test;
 import org.mockito.ArgumentCaptor;
 
@@ -17,62 +18,63 @@
 
 public class GetPromotedAppsUseCaseTest {
 
-    @Test
-    public void invokeCallsRepository() {
-        HomeRepository repository = mock(HomeRepository.class);
-        GetPromotedAppsUseCase useCase = new GetPromotedAppsUseCase(repository);
+    private HomeRepository repository;
+    private GetPromotedAppsUseCase useCase;
+    private GetPromotedAppsUseCase.Callback callback;
+
+    @Before
+    public void setUp() {
+        repository = mock(HomeRepository.class);
+        useCase = new GetPromotedAppsUseCase(repository);
+        callback = mock(GetPromotedAppsUseCase.Callback.class);
+    }
 
-        useCase.invoke(apps -> {});
+    @Test
+    public void invokeRequestsPromotedAppsFromRepository() {
+        useCase.invoke(callback);
 
         verify(repository).fetchPromotedApps(any());
     }
 
     @Test
-    public void invokeReturnsAppsThroughCallback() {
-        HomeRepository repository = mock(HomeRepository.class);
-        GetPromotedAppsUseCase useCase = new GetPromotedAppsUseCase(repository);
-        GetPromotedAppsUseCase.Callback callback = mock(GetPromotedAppsUseCase.Callback.class);
+    public void invokeForwardsRepositoryResultsToCallback() {
+        ArgumentCaptor<HomeRepository.PromotedAppsCallback> captor =
+                ArgumentCaptor.forClass(HomeRepository.PromotedAppsCallback.class);
 
         useCase.invoke(callback);
 
-        ArgumentCaptor<HomeRepository.PromotedAppsCallback> captor =
-                ArgumentCaptor.forClass(HomeRepository.PromotedAppsCallback.class);
         verify(repository).fetchPromotedApps(captor.capture());
+        List<PromotedApp> promotedApps = Collections.singletonList(
+                new PromotedApp("App", "package", "icon")
+        );
 
-        List<PromotedApp> apps = List.of(new PromotedApp("App", "pkg", "icon"));
-        captor.getValue().onResult(apps);
+        captor.getValue().onResult(promotedApps);
 
-        verify(callback).onResult(apps);
+        verify(callback).onResult(promotedApps);
     }
 
     @Test
-    public void invokePropagatesEmptyResults() {
-        HomeRepository repository = mock(HomeRepository.class);
-        GetPromotedAppsUseCase useCase = new GetPromotedAppsUseCase(repository);
-        GetPromotedAppsUseCase.Callback callback = mock(GetPromotedAppsUseCase.Callback.class);
+    public void invokeForwardsEmptyList() {
+        ArgumentCaptor<HomeRepository.PromotedAppsCallback> captor =
+                ArgumentCaptor.forClass(HomeRepository.PromotedAppsCallback.class);
 
         useCase.invoke(callback);
 
-        ArgumentCaptor<HomeRepository.PromotedAppsCallback> captor =
-                ArgumentCaptor.forClass(HomeRepository.PromotedAppsCallback.class);
         verify(repository).fetchPromotedApps(captor.capture());
+        List<PromotedApp> promotedApps = Collections.emptyList();
 
-        List<PromotedApp> apps = Collections.emptyList();
-        captor.getValue().onResult(apps);
+        captor.getValue().onResult(promotedApps);
 
-        verify(callback).onResult(apps);
+        verify(callback).onResult(promotedApps);
     }
 
     @Test
-    public void invokePropagatesNullResults() {
-        HomeRepository repository = mock(HomeRepository.class);
-        GetPromotedAppsUseCase useCase = new GetPromotedAppsUseCase(repository);
-        GetPromotedAppsUseCase.Callback callback = mock(GetPromotedAppsUseCase.Callback.class);
+    public void invokeForwardsNullList() {
+        ArgumentCaptor<HomeRepository.PromotedAppsCallback> captor =
+                ArgumentCaptor.forClass(HomeRepository.PromotedAppsCallback.class);
 
         useCase.invoke(callback);
 
-        ArgumentCaptor<HomeRepository.PromotedAppsCallback> captor =
-                ArgumentCaptor.forClass(HomeRepository.PromotedAppsCallback.class);
         verify(repository).fetchPromotedApps(captor.capture());
 
         captor.getValue().onResult(null);
@@ -81,12 +83,10 @@ public void invokePropagatesNullResults() {
     }
 
     @Test
-    public void invokePropagatesRepositoryException() {
-        HomeRepository repository = mock(HomeRepository.class);
-        GetPromotedAppsUseCase useCase = new GetPromotedAppsUseCase(repository);
-        GetPromotedAppsUseCase.Callback callback = mock(GetPromotedAppsUseCase.Callback.class);
-        doThrow(new IllegalStateException("failure"))
-                .when(repository).fetchPromotedApps(any());
+    public void invokePropagatesRepositoryExceptions() {
+        doThrow(new IllegalStateException("failed"))
+                .when(repository)
+                .fetchPromotedApps(any());
 
         assertThrows(IllegalStateException.class, () -> useCase.invoke(callback));
         verify(repository).fetchPromotedApps(any());