diff --git a/api/models/app.go b/api/models/app.go
index 25c552c1b..03505275e 100644
--- a/api/models/app.go
+++ b/api/models/app.go
@@ -13,11 +13,12 @@ var (
 	ErrAppsGet              = errors.New("Could not get app from datastore")
 	ErrAppsList             = errors.New("Could not list apps from datastore")
 	ErrAppsMissingNew       = errors.New("Missing new application")
+	ErrAppsNameImmutable    = errors.New("Could not update app - name is immutable")
 	ErrAppsNotFound         = errors.New("App not found")
 	ErrAppsNothingToUpdate  = errors.New("Nothing to update")
 	ErrAppsRemoving         = errors.New("Could not remove app from datastore")
-	ErrDeleteAppsWithRoutes = errors.New("Cannot remove apps with routes")
 	ErrAppsUpdate           = errors.New("Could not update app")
+	ErrDeleteAppsWithRoutes = errors.New("Cannot remove apps with routes")
 	ErrUsableImage          = errors.New("Image not found")
 )
 
diff --git a/api/server/apps_test.go b/api/server/apps_test.go
index a46f979f7..e83b2eecc 100644
--- a/api/server/apps_test.go
+++ b/api/server/apps_test.go
@@ -220,6 +220,13 @@ func TestAppUpdate(t *testing.T) {
 				Name: "myapp",
 			}},
 		}, "/v1/apps/myapp", `{ "app": { "config": { "test": "1" } } }`, http.StatusOK, nil},
+
+		// Addresses #380
+		{&datastore.Mock{
+			Apps: []*models.App{{
+				Name: "myapp",
+			}},
+		}, "/v1/apps/myapp", `{ "app": { "name": "othername" } }`, http.StatusForbidden, nil},
 	} {
 		rnr, cancel := testRunner(t)
 		router := testRouter(test.mock, &mqs.Mock{}, rnr, tasks)
diff --git a/api/server/apps_update.go b/api/server/apps_update.go
index bb3925d84..2910d3c29 100644
--- a/api/server/apps_update.go
+++ b/api/server/apps_update.go
@@ -28,6 +28,12 @@ func handleAppUpdate(c *gin.Context) {
 		return
 	}
 
+	if wapp.App.Name != "" {
+		log.Debug(models.ErrAppsNameImmutable)
+		c.JSON(http.StatusForbidden, simpleError(models.ErrAppsNameImmutable))
+		return
+	}
+
 	wapp.App.Name = c.Param("app")
 
 	err = Api.FireAfterAppUpdate(ctx, wapp.App)
diff --git a/docs/apps.md b/docs/apps.md
index f9fb020f4..fdc8b3901 100644
--- a/docs/apps.md
+++ b/docs/apps.md
@@ -27,4 +27,9 @@ curl -H "Content-Type: application/json" -X POST -d '{
         }
     }
 }' http://localhost:8080/v1/apps
-```
\ No newline at end of file
+```
+
+## Notes
+
+App names are immutable. When doing `PUT` calls, keep in mind that although you
+are able to update an app's configuration set, you cannot really rename it.
\ No newline at end of file
diff --git a/docs/swagger.yml b/docs/swagger.yml
index 460f161dd..16d7653b4 100644
--- a/docs/swagger.yml
+++ b/docs/swagger.yml
@@ -116,7 +116,7 @@ paths:
           schema:
             $ref: '#/definitions/Error'
     put:
-      summary: "Create/update a app."
+      summary: "Updates an app."
       description: "You can set app level settings here. "
       tags:
         - Apps