Homekit in a trailer without WiFi?

[pgoelz]

I have a rather specialized question and I can't find any definitive answers....

When we trailer camp, I would like to use a couple Homekit outlet switches to control my iPhone and iPad chargers based on state of charge. This of course works fine at home with WiFi and the internet. But in the trailer, we have no internet connected WiFi and will be using cell data.

I can of course bring a router with me so the outlet switches will have WiFi, but the router will not be connected to the internet so my iPhone on cell data will not be able to communicate with the outlet switches.

Is there some way to make this work..... iPhone on cell data, with a router present but not connected to the internet? For example, are there outlet switches that use BT instead of WiFi that an automation running in my iPhone and iPad can control without WiFi? I know BT switches exist but I can't tell from what I read whether they can be controlled with an automation similar to Homekit devices.

 

[pgoelz]

OK, for the benefit of anyone else researching this I'll answer my own question. I ran across this trick (steps 4, 5 and 6) while researching this issue. These steps will refer to operation in a trailer but they apply to any location away from your home WiFi where you want temporary control of local Homekit devices while retaining a cell data connection.

1. Bring with you any of your Homekit devices that you would like to use. These should be already configured for your home WiFi.

2. In the trailer, set up a standard router with the same AP name as your home router and turn it on. This will create a WiFi network of the same name as your home WiFi and your Homekit devices will connect to it.

3. On your iPhone, go to SETTINGS > WIFI and connect to the router. At this point, you will be able to control your local Homekit devices as long as you are within WiFi range. Because you are connected to WiFi but the router does not have an internet connection, you will NOT have a data connection on your phone. Don't worry......

4. On your iPhone, go to SETTINGS > WiFi and tap the "i" next to your router's name. Scroll down to the IP address and subnet mask and write them down.

5. On that same page, tap "configure IP", change AUTOMATIC to MANUAL.

6. For IP address and subnet mask, enter the IP address and subnet mask from step 4. Leave the "router" field blank.

Voila! You now will have both a WiFi connection AND a cellular data connection on your phone. While within range of the WiFi network, traffic for the Homekit devices will be passed over the WiFi network. If you move out of WiFi range, you will loose connection to the Homekit devices. However, you will have cell data on your phone regardless of whether or not you are connected to the WiFi network. AND, your phone can still act as a hotspot for other devices.

When you return home, simply change the "configure IP" setting back to automatic.

There may be a simpler method to retain simultaneous connections to WiFi and cell data but I have not found it.

 

[Squillace]

Or you can buy a 4G/5G router with a SIM card. It will cost you more, sure, but I'm sure there are cheap internet plans without subscription and working on a prepay basis.