diff --git a/onionshare/common.py b/onionshare/common.py
index 176c7931..a2cc4b7d 100644
--- a/onionshare/common.py
+++ b/onionshare/common.py
@@ -20,7 +20,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 import base64
 import hashlib
 import inspect
-import math
 import os
 import platform
 import random
@@ -146,14 +145,14 @@ def human_readable_filesize(b):
     """
     thresh = 1024.0
     if b < thresh:
-        return '{0:.1f} B'.format(b)
-    units = ['KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB']
+        return '{:.1f} B'.format(b)
+    units = ('KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB')
     u = 0
     b /= thresh
     while b >= thresh:
         b /= thresh
         u += 1
-    return '{0:.1f} {1:s}'.format(round(b, 1), units[u])
+    return '{:.1f} {}'.format(b, units[u])
 
 
 def format_seconds(seconds):
diff --git a/onionshare/onion.py b/onionshare/onion.py
index efcd7ae2..aedd98c2 100644
--- a/onionshare/onion.py
+++ b/onionshare/onion.py
@@ -433,6 +433,13 @@ class Onion(object):
         self.stealth = False
         self.service_id = None
 
+        try:
+            # Delete the temporary tor data directory
+            self.tor_data_directory.cleanup()
+        except AttributeError:
+            # Skip if cleanup was somehow run before connect
+            pass
+
     def get_tor_socks_port(self):
         """
         Returns a (address, port) tuple for the Tor SOCKS port
diff --git a/onionshare/settings.py b/onionshare/settings.py
index 18e7dd26..408c8bdc 100644
--- a/onionshare/settings.py
+++ b/onionshare/settings.py
@@ -18,10 +18,13 @@ You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 """
 
-import platform, os, json
+import json
+import os
+import platform
 
 from . import strings, common
 
+
 class Settings(object):
     """
     This class stores all of the settings for OnionShare, specifically for how
@@ -95,7 +98,7 @@ class Settings(object):
             try:
                 common.log('Settings', 'load', 'Trying to load {}'.format(self.filename))
                 with open(self.filename, 'r') as f:
-                    self._settings = json.loads(f.read())
+                    self._settings = json.load(f)
                     self.fill_in_defaults()
             except:
                 pass
diff --git a/onionshare/strings.py b/onionshare/strings.py
index 9b26b4b1..7a1f08a5 100644
--- a/onionshare/strings.py
+++ b/onionshare/strings.py
@@ -17,17 +17,19 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 """
-import json, locale, os
+import json
+import locale
+import os
 
 strings = {}
 
+
 def load_strings(common, default="en"):
     """
     Loads translated strings and fallback to English
     if the translation does not exist.
     """
     global strings
-    p = common.get_platform()
 
     # find locale dir
     locale_dir = common.get_resource_path('locale')
@@ -37,10 +39,9 @@ def load_strings(common, default="en"):
     for filename in os.listdir(locale_dir):
         abs_filename = os.path.join(locale_dir, filename)
         lang, ext = os.path.splitext(filename)
-        if abs_filename.endswith('.json'):
+        if ext == '.json':
             with open(abs_filename, encoding='utf-8') as f:
-                lang_json = f.read()
-                translations[lang] = json.loads(lang_json)
+                translations[lang] = json.load(f)
 
     strings = translations[default]
     lc, enc = locale.getdefaultlocale()
diff --git a/onionshare/web.py b/onionshare/web.py
index aec86bf4..1d8237da 100644
--- a/onionshare/web.py
+++ b/onionshare/web.py
@@ -17,12 +17,22 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 """
+
+import hmac
+import logging
+import mimetypes
+import os
+import queue
+import socket
+import sys
+import tempfile
 from distutils.version import StrictVersion as Version
-import queue, mimetypes, platform, os, sys, socket, logging, hmac
 from urllib.request import urlopen
 
-from flask import Flask, Response, request, render_template_string, abort, make_response
-from flask import __version__ as flask_version
+from flask import (
+    Flask, Response, request, render_template_string, abort, make_response,
+    __version__ as flask_version
+)
 
 from . import strings, common
 
@@ -56,6 +66,7 @@ security_headers = [
     ('Server', 'OnionShare')
 ]
 
+
 def set_file_info(filenames, processed_size_callback=None):
     """
     Using the list of filenames being shared, fill in details that the web
@@ -115,6 +126,8 @@ def add_request(request_type, path, data=None):
 
 
 slug = None
+
+
 def generate_slug():
     global slug
     slug = common.build_slug()
@@ -123,12 +136,16 @@ download_count = 0
 error404_count = 0
 
 stay_open = False
+
+
 def set_stay_open(new_stay_open):
     """
     Set stay_open variable.
     """
     global stay_open
     stay_open = new_stay_open
+
+
 def get_stay_open():
     """
     Get stay_open variable.
@@ -138,6 +155,8 @@ def get_stay_open():
 
 # Are we running in GUI mode?
 gui_mode = False
+
+
 def set_gui_mode():
     """
     Tell the web service that we're running in GUI mode
@@ -145,21 +164,19 @@ def set_gui_mode():
     global gui_mode
     gui_mode = True
 
+
 def debug_mode():
     """
     Turn on debugging mode, which will log flask errors to a debug file.
     """
-    if platform.system() == 'Windows':
-        temp_dir = os.environ['Temp'].replace('\\', '/')
-    else:
-        temp_dir = '/tmp/'
-
-    log_handler = logging.FileHandler('{0:s}/onionshare_server.log'.format(temp_dir))
+    temp_dir = tempfile.gettempdir()
+    log_handler = logging.FileHandler(
+        os.path.join(temp_dir, 'onionshare_server.log'))
     log_handler.setLevel(logging.WARNING)
     app.logger.addHandler(log_handler)
 
-def check_slug_candidate(slug_candidate, slug_compare = None):
-    global slug
+
+def check_slug_candidate(slug_candidate, slug_compare=None):
     if not slug_compare:
         slug_compare = slug
     if not hmac.compare_digest(slug_compare, slug_candidate):
@@ -170,6 +187,7 @@ def check_slug_candidate(slug_candidate, slug_compare = None):
 # one download at a time.
 download_in_progress = False
 
+
 @app.route("/<slug_candidate>")
 def index(slug_candidate):
     """
@@ -185,7 +203,7 @@ def index(slug_candidate):
     deny_download = not stay_open and download_in_progress
     if deny_download:
         r = make_response(render_template_string(open(common.get_resource_path('html/denied.html')).read()))
-        for header,value in security_headers:
+        for header, value in security_headers:
             r.headers.set(header, value)
         return r
 
@@ -198,15 +216,17 @@ def index(slug_candidate):
         filename=os.path.basename(zip_filename),
         filesize=zip_filesize,
         filesize_human=common.human_readable_filesize(zip_filesize)))
-    for header,value in security_headers:
+    for header, value in security_headers:
         r.headers.set(header, value)
     return r
 
+
 # If the client closes the OnionShare window while a download is in progress,
 # it should immediately stop serving the file. The client_cancel global is
 # used to tell the download function that the client is canceling the download.
 client_cancel = False
 
+
 @app.route("/<slug_candidate>/download")
 def download(slug_candidate):
     """
@@ -332,10 +352,11 @@ def page_not_found(e):
             print(strings._('error_rate_limit'))
 
     r = make_response(render_template_string(open(common.get_resource_path('html/404.html')).read()))
-    for header,value in security_headers:
+    for header, value in security_headers:
         r.headers.set(header, value)
     return r
 
+
 # shutting down the server only works within the context of flask, so the easiest way to do it is over http
 shutdown_slug = common.random_string(16)