diff --git a/blockchainauth/auth_request.py b/blockchainauth/auth_request.py
index 320787b..3a35bb2 100644
--- a/blockchainauth/auth_request.py
+++ b/blockchainauth/auth_request.py
@@ -7,8 +7,11 @@
     :license: MIT, see LICENSE for more details.
 """
 
-import uuid
+from jwt import DecodeError
+import requests
+import requests.exceptions
 import time
+import uuid
 from cryptography.hazmat.backends import default_backend
 from pybitcoin import BitcoinPrivateKey
 from blockchainauth.auth_message import AuthMessage
@@ -31,7 +34,7 @@ class AuthRequest(AuthMessage):
     ]
 
     def __init__(self, private_key, domain_name, manifest_uri=None, redirect_uri=None,
-                 scopes=None, expires_after=None, crypto_backend=default_backend()):
+                 scopes=None, expires_after=None, crypto_backend=default_backend(), **kwargs):
         """ private_key should be provided in HEX, WIF or binary format 
             domain_name should be a valid domain
             manifest_uri should be a valid URI
@@ -79,5 +82,19 @@ def _payload(self):
             payload['iss'] = make_did_from_address(address)
         return payload
 
+    @classmethod
+    def fetch_app_manifest(cls, token):
+        # decode the token
+        try:
+            decoded_token = cls.decode(token)
+        except DecodeError:
+            return None
+
+        try:
+            return requests.get(decoded_token['payload']['manifest_uri']).json()
+        except (requests.exceptions.RequestException, ValueError):
+            # ValueError for non-json responses
+            return None
+
     def redirect_url(self):
         return 'blockstack:' + self.token()
diff --git a/blockchainauth/verification.py b/blockchainauth/verification.py
index 1b88465..64be386 100644
--- a/blockchainauth/verification.py
+++ b/blockchainauth/verification.py
@@ -7,12 +7,15 @@
 """
 
 import requests
+import requests.exceptions
 import time
 import traceback
 from pybitcoin import BitcoinPublicKey
 from blockchainauth.dids import get_address_from_did
 
-NAME_LOOKUP_URL = 'https://explorer-api.appartisan.com/get_name_blockchain_record/'
+LOCALHOST_CORE_API = 'http://localhost:6270'
+EXTERNAL_CORE_API = 'https://core.blockstack.org'
+NAME_LOOKUP_URL = '/v1/names/'
 
 
 def do_signatures_match_public_keys(token, tokenizer, decoded_token):
@@ -55,14 +58,32 @@ def do_public_keys_match_username(token, tokenizer, decoded_token):
         traceback.print_exc()
         return False
 
-    if not payload.get('username', None) or not NAME_LOOKUP_URL:
+    if not payload.get('username', None):
         return True
 
     username = payload['username']
-    url = NAME_LOOKUP_URL.rstrip('/') + '/' + username
 
     # get publicly available address and address from payload
-    response = requests.get(url).json()
+    # first try from localhost
+    url = LOCALHOST_CORE_API + NAME_LOOKUP_URL + username
+    try:
+        response = requests.get(url).json()
+    except (requests.exceptions.RequestException, ValueError):
+        # ValueError for non-json responses
+        response = None
+
+    # if failed try from public Core API
+    if not response:
+        url = EXTERNAL_CORE_API + NAME_LOOKUP_URL + username
+        try:
+            response = requests.get(url).json()
+        except (requests.exceptions.RequestException, ValueError):
+            # ValueError for non-json responses
+            response = None
+
+    if not response:
+        return False
+
     try:
         address_from_issuer = get_address_from_did(payload.get('iss', ''))
     except ValueError:
diff --git a/setup.py b/setup.py
index 47304bf..bc4d78d 100644
--- a/setup.py
+++ b/setup.py
@@ -8,7 +8,7 @@
 
 setup(
     name='blockchainauth',
-    version='0.3.1',
+    version='0.3.2',
     url='https://github.com/blockstack/blockchain-auth-python',
     license='MIT',
     author='Blockstack Developers',
diff --git a/tests/unit_tests.py b/tests/unit_tests.py
index 1a6952c..b23fef6 100644
--- a/tests/unit_tests.py
+++ b/tests/unit_tests.py
@@ -19,7 +19,7 @@
     REQUEST_SAMPLE_ENCODED_TOKEN, REQUEST_SAMPLE_DECODED_TOKEN,\
     RESPONSE_SAMPLE_ENCODED_TOKEN, RESPONSE_SAMPLE_DECODED_TOKEN, RYAN_PROFILE
 from blockchainauth.tokenizer import Tokenizer
-from blockchainauth.verification import do_public_keys_match_username, NAME_LOOKUP_URL
+from blockchainauth.verification import do_public_keys_match_username, LOCALHOST_CORE_API, NAME_LOOKUP_URL
 
 
 class AuthRequestTest(unittest.TestCase):
@@ -96,7 +96,7 @@ def test_auth_response_token_encoding(self):
 
         # with username
         with requests_mock.mock() as m:
-            m.get(NAME_LOOKUP_URL.rstrip('/') + '/' + self.username,
+            m.get(LOCALHOST_CORE_API + NAME_LOOKUP_URL + self.username,
                   text=json.dumps({'address': self.public_key.address()}))
             auth_response = AuthResponse(self.private_key_hex, RYAN_PROFILE, self.username)
             auth_response_token = auth_response.token()