iOS Companion App intermittently fails to connect over Vodafone cellular network
Environment
-
iPhone: iPhone 13 Pro
-
iOS: 26.6.1
-
Home Assistant Companion App: 2026.9.0 (2874)
-
Home Assistant: Home Assistant Green
-
Remote access: Home Assistant Cloud / Nabu Casa
-
Mobile operator: Vodafone Italy
Problem
The Home Assistant iOS Companion App intermittently fails to connect to my Home Assistant when my iPhone is connected to the Vodafone cellular network.
The app shows:
Connected via Remote UI URL
but it is unable to retrieve the Home Assistant state and eventually fails.
The diagnostic log repeatedly shows:
Failed to fetch states on server Casa
I have also seen an error indicating that the secure TLS connection failed.
Important comparison
The problem can be reproduced depending on the network connection:
-
iPhone 13 Pro + Vodafone cellular → Companion App fails intermittently
-
Same iPhone 13 Pro + same Companion App + Iliad hotspot → Companion App works
-
Same iPhone 13 Pro + Vodafone cellular + Safari → Home Assistant Cloud works correctly
This is the most important point.
The Home Assistant Cloud URL is reachable over Vodafone because Safari connects successfully.
The Companion App also works correctly on the same iPhone when using the Iliad hotspot.
This seems to indicate a problem specifically involving the Companion App’s network/TLS/WebSocket connection over the Vodafone cellular network.
Troubleshooting already performed
-
iPhone restarted.
-
Home Assistant restarted.
-
Companion App completely uninstalled and reinstalled twice.
-
Local Network permission: enabled.
-
Cellular Data permission: enabled for Home Assistant.
-
Location permission: Always.
-
Home Assistant Cloud is active and works correctly through Safari.
-
Safari tested on the same iPhone and Vodafone connection: works correctly.
-
Same iPhone tested through an Iliad hotspot: Companion App works correctly.
The Companion App is fully updated to version 2026.9.0 (2874).
Configuration
-
Internal URL: configured for local access.
-
External URL: Home Assistant Cloud.
-
Connect via Cloud: enabled.
-
Connection security level: Most secure.
Question
Could this be related to Vodafone’s IPv6, DNS, TLS or WebSocket routing, or possibly to a regression in the current iOS Companion App networking stack?
The key comparison is:
Vodafone + Safari → works
Vodafone + Companion App → fails intermittently
Iliad hotspot + Companion App → works
I would appreciate any advice on whether this is a known issue and what diagnostic information would be useful to identify the cause.