Tag Archives: hotspot

Using your Mac with your iPhone hotspot? Be sure to turn on low data mode!

In the summer, I like to take my MacBook Pro with me and work outdoors. Doing that is entirely dependent upon my T-Mobile hotspot on my iPhone. I had my account maxed out at 16 GB of hotspot data per month, so imagine my surprise today when — one day into a new cycle — I got a notification text that my data had been used up!

I’m still not sure what exactly my Mac was doing, presumably some kind of background iCloud Drive backup, but I managed to use up an entire month’s allotment of bandwidth in extremely short order. I worked with T-Mobile support to get my account bumped up to the absolute maximum 20 GB, but there’s no certain explanation of what it was that used all of that data.

But along the way I discovered the Mac does let you configure “low data mode” specific to each network you connect to. If you find yourself needing to use a hotspot regularly, I would strongly recommend turning on low data mode for that network. To do that with the new Ventura System Settings app, go to WiFi, then under Known Networks click the … icon for your hotspot, and chose Network Settings…

Now here’s where it gets interesting. I turned on the Low data mode toggle about five times and it kept, after a couple of seconds, shutting itself back off. Finally it “stuck.” Now we’ll see over the coming days if it actually makes a difference!

Is T-Mobile bypassing local ad blockers when using your hotspot?

I hate online ads.

That could be the end of the post, but sadly it’s not.

I understand that sites need ad revenue to function. But the online advertising ecosystem is so fundamentally broken that I refuse to participate in it, even to the detriment of the sites whose content I value. It’s possible to run a sustainable business through ads without ruining your site visitors’ experience.

There are various tools you can use to block the most obnoxious ads, but I’ve taken a very direct, hands-on approach. I’ve actually taken the time to view source on sites I visit that go overboard with ads, identify the domain names of the ad servers, and add them to my Mac’s /etc/hosts file so they resolve to localhost (127.0.0.1), effectively killing any ads from those sources.

And it works. I often see “broken image” icons, but all of those hideous animated ads screaming at my eyeballs are gone.

Except when I’m tethering to my phone’s hotspot.

Somehow, when I use my T-Mobile hotspot instead of my home wifi, all of those ads come flooding back. What. Is. Happening.

The only explanation I can think of is that T-Mobile is somehow using a proxy to bypass my local hosts file, but I though the local file always trumped anything else.

I don’t have an answer. But I don’t like it. And perhaps more importantly, if T-Mobile is doing this, what else is it doing with the data I’m sending and receiving over its network?