diff --git a/conf/.env.example b/conf/.env.example
index 56e6509..5c64113 100644
--- a/conf/.env.example
+++ b/conf/.env.example
@@ -16,9 +16,17 @@ APP_ENV=production
 APP_DEBUG=false
 
 # Application key
+# Used for encryption where needed.
+# Run `php artisan key:generate` to generate a valid key.
 APP_KEY=SomeRandomString
 
 # Application URL
+# This must be the root URL that you want to host BookStack on.
+# All URLs in BookStack will be generated using this value
+# to ensure URLs generated are consistent and secure.
+# If you change this in the future you may need to run a command
+# to update stored URLs in the database. Command example:
+# php artisan bookstack:update-url https://old.example.com https://new.example.com
 APP_URL=__APP_URL_DOMAIN__
 
 # Application default language
@@ -41,6 +49,7 @@ DB_PASSWORD=__DB_PWD__
 FILE_UPLOAD_SIZE_LIMIT=100
 
 # Mail system to use
+# Can be 'smtp' or 'sendmail'
 MAIL_DRIVER=smtp
 
 # Mail sender details
@@ -50,8 +59,10 @@ MAIL_FROM=bookstack@__DOMAIN__
 # SMTP mail options
 # These settings can be checked using the "Send a Test Email"
 # feature found in the "Settings > Maintenance" area of the system.
+# For more detailed documentation on mail options, refer to:
+# https://www.bookstackapp.com/docs/admin/email-webhooks/#email-configuration
 MAIL_HOST=localhost
-MAIL_PORT=25
+MAIL_PORT=587
 MAIL_USERNAME=__APP__
 MAIL_PASSWORD=__MAIL_PWD__
 MAIL_ENCRYPTION=null