diff --git a/src/apps.js b/src/apps.js
index 070910016..9bf80facb 100644
--- a/src/apps.js
+++ b/src/apps.js
@@ -697,7 +697,7 @@ function install(data, auditSource, callback) {
     assert.strictEqual(typeof auditSource, 'object');
     assert.strictEqual(typeof callback, 'function');
 
-    assert(data.appStoreId && data.manifest); // manifest is already downloaded
+    assert.strictEqual(typeof data.manifest, 'object'); // manifest is already downloaded
 
     var location = data.location.toLowerCase(),
         domain = data.domain.toLowerCase(),