diff --git a/pisa-btc/pisa/api.py b/pisa-btc/pisa/api.py
index 54a1686..af3ac47 100644
--- a/pisa-btc/pisa/api.py
+++ b/pisa-btc/pisa/api.py
@@ -10,7 +10,7 @@ import json
 from utils.authproxy import AuthServiceProxy
 from conf import BTC_RPC_USER, BTC_RPC_PASSWD, BTC_RPC_HOST, BTC_RPC_PORT
 
-
+# ToDo: #5-add-async-to-api
 app = Flask(__name__)
 HTTP_OK = 200
 HTTP_BAD_REQUEST = 400
diff --git a/pisa-btc/pisa/appointment.py b/pisa-btc/pisa/appointment.py
index bccee5f..af304ee 100644
--- a/pisa-btc/pisa/appointment.py
+++ b/pisa-btc/pisa/appointment.py
@@ -5,8 +5,8 @@ from pisa.encrypted_blob import EncryptedBlob
 class Appointment:
     def __init__(self, locator, start_time, end_time, dispute_delta, encrypted_blob, cipher, hash_function):
         self.locator = locator
-        self.start_time = start_time
-        self.end_time = end_time
+        self.start_time = start_time    # ToDo: #4-standardize-appointment-fields
+        self.end_time = end_time    # ToDo: #4-standardize-appointment-fields
         self.dispute_delta = dispute_delta
         self.encrypted_blob = EncryptedBlob(encrypted_blob)
         self.cipher = cipher
@@ -19,9 +19,7 @@ class Appointment:
 
         return appointment
 
-        # ToDO: We may want to add some additional things to the appointment, like
-        #   minimum fee
-        #   refund to be payed to the user in case of failing
+        # ToDO: #3-improve-appointment-strcuture
 
 
 
diff --git a/pisa-btc/pisa/inspector.py b/pisa-btc/pisa/inspector.py
index 0eb392c..3680717 100644
--- a/pisa-btc/pisa/inspector.py
+++ b/pisa-btc/pisa/inspector.py
@@ -146,7 +146,7 @@ class Inspector:
 
         return rcode, message
 
-    # DISCUSS: ANYTHING TO CHECK HERE?
+    # ToDo: #5-define-checks-encrypted-blob
     def check_blob(self, encrypted_blob):
         message = None
         rcode = 0
@@ -160,7 +160,7 @@ class Inspector:
             rcode = errors.APPOINTMENT_WRONG_FIELD_TYPE
             message = "wrong encrypted_blob data type ({})".format(t)
         elif encrypted_blob == '':
-            # ToDo: We may want to define this to be at least as long as one block of the cipher we are using
+            # ToDo: #5 We may want to define this to be at least as long as one block of the cipher we are using
             rcode = errors.APPOINTMENT_WRONG_FIELD
             message = "wrong encrypted_blob"
         if self.debug and message:
diff --git a/pisa-btc/pisa/zmq_subscriber.py b/pisa-btc/pisa/zmq_subscriber.py
index 78a44de..23a411a 100644
--- a/pisa-btc/pisa/zmq_subscriber.py
+++ b/pisa-btc/pisa/zmq_subscriber.py
@@ -2,7 +2,7 @@ import zmq
 import binascii
 from conf import FEED_PROTOCOL, FEED_ADDR, FEED_PORT
 
-
+# ToDo: #7-add-async-back-to-zmq
 class ZMQHandler:
     """ Adapted from https://github.com/bitcoin/bitcoin/blob/master/contrib/zmq/zmq_sub.py"""
     def __init__(self, parent):