diff --git a/README.md b/README.md
index 279ff6c..feaeb2a 100644
--- a/README.md
+++ b/README.md
@@ -8,17 +8,18 @@
 [![commit-activity](https://img.shields.io/github/commit-activity/m/marzzzello/appstore_crawler.svg?style=for-the-badge)](https://img.shields.io/github/commit-activity/m/marzzzello/appstore_crawler.svg?style=for-the-badge)
 [![Mastodon Follow](https://img.shields.io/mastodon/follow/103207?domain=https%3A%2F%2Fsocial.tchncs.de&logo=mastodon&style=for-the-badge)](https://social.tchncs.de/@marzzzello)
 
-# Apple Appstore Crawler
+# Apple App Store Crawler
 
-This crawler is based on [scrapy](https://docs.scrapy.org/en/latest/) and can download the IDs of all apps in appstore.
+This crawler is based on [scrapy](https://docs.scrapy.org/en/latest/) and can download the IDs of all apps in the Apple App Store.
 It can also download the metadata for a list of IDs.
 
 ### Get IDs
 
 The crawler uses `https://apps.apple.com/{country}/genre/ios/id36` to get the categories and IDs by crawling all categories, letters and pages.
+Since the webserver has no rate limiting, it is not needed to set a delay. A full crawl needs about 20 minutes (10-15 pages/second).
 
 ```sh
-scrapy crawl -L INFO appstore_ids -a saveurls=False -a country=us -a level=1 -O out_ids.jl
+scrapy crawl -L INFO appstore_ids -a saveurls=False -a country=us -a level=0 -O out_ids.jl
 ```
 
 Parameters:
@@ -100,3 +101,4 @@ DOWNLOAD_DELAY_IDS = 0.0
 ```
 
 The default delays are tested and should work well.
+With the amp multi method and default settings the retrieval of metadata for 1 million apps needs about 3 hours.
diff --git a/appstore/spiders/appstore_ids.py b/appstore/spiders/appstore_ids.py
index ab28dfa..64b052e 100644
--- a/appstore/spiders/appstore_ids.py
+++ b/appstore/spiders/appstore_ids.py
@@ -57,8 +57,9 @@ def parse_main(self, response):
             )
 
         main_categories_without_sub_urls = response.css('a.top-level-genre:only-child::attr(href)').getall()
-        # main_categories_with_sub = response.css('a.top-level-genre:not(:only-child)::attr(href)').getall()
+        main_categories_with_sub = response.css('a.top-level-genre:not(:only-child)::attr(href)').getall()
         # subcategories = response.css('ul.top-level-subgenres a::attr(href)').getall()
+        sub_categories_urls = []
 
         # main categorie that has multiple subcategories
         for categorie in response.css('a.top-level-genre:not(:only-child)'):
@@ -71,6 +72,7 @@ def parse_main(self, response):
                         'url': subcat.attrib['href'],
                     }
                 )
+                sub_categories_urls.append(subcat.attrib['href'])
 
             categories.append(
                 {
@@ -87,6 +89,12 @@ def parse_main(self, response):
             for url in main_categories_without_sub_urls:
                 url = response.urljoin(url)
                 yield scrapy.Request(url, callback=self.parse_categorie)
+            for url in sub_categories_urls:
+                url = response.urljoin(url)
+                yield scrapy.Request(url, callback=self.parse_categorie)
+            for url in main_categories_with_sub:
+                url = response.urljoin(url)
+                yield scrapy.Request(url, callback=self.parse_categorie)
 
     def parse_categorie(self, response):
         cat_id = response.url.split('/id')[1]
@@ -110,7 +118,7 @@ def parse_categorie(self, response):
                 yield scrapy.Request(url, callback=self.parse_categorie_letter)
 
     def parse_categorie_letter(self, response):
-        cat_id, end = response.url.split('/id')[1].split('?letter=')
+        cat_id, end = response.url.split('/id')[-1].split('?letter=')
         if len(end) == 1:
             letter = end
             page = '0'
@@ -119,7 +127,7 @@ def parse_categorie_letter(self, response):
 
         print(f'Parsing {cat_id} {letter} {page:>3};', end=' ')
         print(
-            f'Done {num_fmt(self._pages):>4}/~15k pages, {num_fmt(self._apps):>5}/~1.6M apps   ',
+            f'Done {num_fmt(self._pages):>4}/~20k pages, {num_fmt(self._apps):>5}/~2.3M apps   ',
             end='\r',
         )
 
diff --git a/appstore/spiders/appstore_metadata.py b/appstore/spiders/appstore_metadata.py
index bc9fc35..5f982cb 100644
--- a/appstore/spiders/appstore_metadata.py
+++ b/appstore/spiders/appstore_metadata.py
@@ -122,13 +122,13 @@ def scrape_metadata(self):
         base_url_ua = f'https://apps.apple.com/{self._country}/app/'
         header_ua = {'User-Agent': self._UA}
 
-        while len(self._ids_amp) > 1 or (self._use_UA and len(self._ids_ua) > 1):
-            if self._use_UA and len(self._ids_ua) > 1:
+        while len(self._ids_amp) > 0 or (self._use_UA and len(self._ids_ua) > 0):
+            if self._use_UA and len(self._ids_ua) > 0:
                 app_id = self._ids_ua.pop()
                 url_ua = base_url_ua + 'id' + str(app_id)
                 yield scrapy.Request(url_ua, self.parse_ua, headers=header_ua)
 
-            if len(self._ids_amp) > 1:
+            if len(self._ids_amp) > 0:
                 if self._amp_single:
                     app_id = self._ids_amp.pop()
                     url_amp = base_url_amp + '/' + str(app_id) + '?' + self.get_params()
@@ -263,7 +263,7 @@ def get_params(self, ids={}):
             'limit[reviews]': 20,
             'l': self._locale,
         }
-        if ids is {}:
+        if ids == {}:
             del params['ids']
         else:
             del params['include']