Added admin ui menu callback and setting form.

googleanalytics.admin.inc

+<?php
+
+function googleanalytics_admin_settings($form, &$form_state) {
+  $config = config('googleanalytics.settings');
+
+  $form['trackingId'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Google Analytics Tracking ID'),
+    '#default_value' => $config->get('trackingId'),
+    '#description' => t('Enter Your Google Analytics Tracking ID. Format should be UA-12345678-9'),
+  );
+
+  return system_config_form($form, $form_state);
+}
+
+function googleanalytics_admin_settings_submit($form, $form_state) {
+  config('googleanalytics.settings')
+    ->set('trackingId', $form_state['values']['trackingId'])
+    ->save();
+}

googleanalytics.module

@@ -10,11 +10,8 @@
  */
 
 function googleanalytics_page_build(&$page) {
-  // note : to keep api codes out of the repo, add config files to .gitignore
   $config = config('googleanalytics.settings');
   $googleanalytics_tracking_id = $config->get('trackingId');
-  // dpm($config);
-  // dpm($googleanalytics_tracking_id);
 
   // Seems like the attached isn't working, possibly because this is in-line code
   // $page['#attached']['js'][$script] = array('every_page' => TRUE);
@@ -22,7 +19,22 @@ function googleanalytics_page_build(&$page) {
   drupal_add_js(_googleanalytics_get_code($googleanalytics_tracking_id),
     array('type' => 'inline', 'scope' => 'footer', 'weight' => 5)
   );
-  // dpm($page);
+}
+
+/**
+ * Implements hook_menu().
+ */
+function googleanalytics_menu() {
+  $items['admin/config/statistics/googleanalytics'] = array(
+    'title' => 'Google Analytics Lite settings',
+    'description' => 'Google Analytics Integration Settings.',
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('googleanalytics_admin_settings'),
+    'file' => 'googleanalytics.admin.inc',
+    'access arguments' => array('administer site configuration'),
+  );
+
+  return $items;
 }
 
 /*