diff --git a/bin/dev b/bin/dev
index f5e4d8d676..05032e7c36 100755
--- a/bin/dev
+++ b/bin/dev
@@ -45,4 +45,4 @@ else
   echo "Login with david@example.com to: http://fizzy.localhost:$PORT/"
 fi
 
-./bin/rails server -p $PORT
+./bin/rails server -b 0.0.0.0 -p $PORT
diff --git a/config/environments/development.rb b/config/environments/development.rb
index 6088b670d3..ace7b503d7 100644
--- a/config/environments/development.rb
+++ b/config/environments/development.rb
@@ -89,8 +89,9 @@
     "fizzy.localhost",
     "localhost",
     "127.0.0.1",
-    /fizzy-\d+/,  # review apps: fizzy-123, fizzy-456:3000
-    /.*\.ts\.net/ # tailscale serve: hostname.tail1234.ts.net
+    /fizzy-\d+/,   # review apps: fizzy-123, fizzy-456:3000
+    /.*\.ts\.net/, # tailscale serve: hostname.tail1234.ts.net
+    /.*\.nip\.io/  # nip.io for mobile apps
   ]
 
   # Canonical host for mailer URLs (emails always link here, not personal Tailscale URLs)