2025 mobile data upgrade

September 25, 2025

This will be a list-heavy post; I’m trying to get a ton of information down while it’s fresh in my head.

TL;DR

carry phone is on wifi 95% of the time so it has the cheapest-possible AT&T MVNO SIM.
5G router with main Verizon-based sim and failover “physical” eSIM for other networks. Connected to roof-mounted external antenna. On public wifi anytime that’s available.

goals

increase coverage by
- replacing the Cudy LTE router¹ with one that supports more mobile data bands²
- getting better reception with external antennas (both outside the vehicle and higher up)
- having a budget-friendly way to access all three major carriers when needed (see eSIM section below)
combine mobile data and wifi repeating on the same GL.iNet device. The Cudy has wifi repeater functionality that, you know, works. But it’s slow, clunky, and can only remember one AP. GL-iNet’s repeater interface is fast, highly-configurable, and if it has a limit on remembered APs I haven’t hit it.
move this combined router out of sight and out of the way. Since it’s connected to external ants it will no longer need a clear view out window glass.

The observant reader will notice I did not mention speed. I ruthlessly police my bandwidth usage, perhaps because I started out on an acoustically-coupled 110 baud modem. :-) I don’t stream videos for entertainment, and defer updates and downloads until the next time I am around public wifi. If my connection is dodgy I turn off browser images with the Fast Image Blocker plugin. Even when images are enabled uBlock Origin blocks any media over 50KB. If I want to see a given image I can explicitly click on it…

the setup

Here is the 2025 setup

router

The Spitz AX x3000 router handles mobile data duties and distributes the connection by wifi and Ethernet as needed.

Whenever a known wifi SSID is present it switches over to repeating that instead of using cell data. GL-iNet’s wifi repeating interface is excellent, and is the main reason I bought their router instead of a competitor.³

The router has a single modem but can failover between cards in the dual sim slots. Slot 1 is my main “unlimited” Verizon-based carrier. SIM 2 holds is a “physical” eSIM card that allows quick changes on the fly if Verizon isn’t available. See below.

features I won’t use

multi-WAN (combining wifi and mobile data, for example). When I’m latched onto wifi that’s all I use.
AdGuard home. I just use AdGuard’s DNS as primary and google’s as secondary. Less configurable but all the CPU strain is offloaded to their DNS service.
QOS - I haven’t had anyone to share signal with in a few years, but if I did roll out the guest wifi I’d limit the bandwidth on it.

limitations

The Spitz AX focuses on Sub6 bands which rules out mmWave (UW). With one technical exception:

Verizon classifies both n77 and mmWave bands n260 and n261 as UW. The Spitz is not capable of n260 and n261 but IS capable of n77.

It has little bearing on my use since I’m more interested in rural connectivity than rip-roaring urban speeds.

antenna

This decision was tough. I wanted:

no less dB gain than the stock ants. Even if they are the same gain the ants will be up higher and outside the van.
4x4 4g/5G to maximize the Spitz’ reach
- rated down to 600MHz to make good use of band 71. For some reason most 5G ants seem to rated only ≥700MHz.
2x2 dual-band wifi to latch on to distant APs and also to distribute mobile data backhaul around my campsites.
preferably in one dome so I only have to drill one hole
preferably white to reduce heating from the sun and to be less obvious on the white van
shouldn’t cost more than the router (some do!)
must fit on a flat section of the camper’s roof; some are too wide and encroach on roof ribs.

I picked this 6-in-1 from Proxicast.

They don’t make it in white but their docs say it’s paintable.

eSIMs on a physical eSIM card

SIM cards are the traditional ones you know and either love or hate.

eSIMs are:

… a form of SIM card that is embedded directly into a device as software installed onto an eUICC chip. (Wikipedia

A physical eSIM is a mix between the two – the eSIM magic is embedded in a normal-looking SIM card. They have some advantages:

they can add eSIM functionality to a device that does not natively support eSIMs
they can store multiple eSIM profiles on the same card, and choose between them at will
they facilitate transferring the eSIM to a different device

The main disadvantage seems to be that an internet connection is required to get the eSIM profile loaded. A bit of a Catch-22 if one didn’t plan ahead.⁴ For this reason the makers of physical eSIM card often preload it with just enough data to get you through the purchase and activation.

The Spitz and some other GL-iNet routers have a GUI for configuring and installing eSIMs (announcement). The easiest way is to use a QR code that the seller emails or otherwise makes available to you for this purpose.

Glinet sells a version but it seems the ones from EIOTCLUB, 9esim, and similar work, too. Lots of discussion on the Glinet forums on this subject.

an aside on eSIM plans

There are a few different kinds of eSIM plans. Some of them are useful in my use case and some are not

defined data plan (“5GB”) that does not expire. Expensive by the GB but the lack of expiration makes it useful as a fallback for shorter outages.
defined data plan (“5GB”) for a defined period (“7 days”). This can be least expensive when both the amount of data and expiration date meet your needs. Remember, these can expire by either bandwidth or date, whichever comes first. These would be useful for longer stays in an area with no coverage from your primary carrier.
a subtype of the above that is very cheap and very limited; these are used for testing a network before committing to a pricier plan.
unlimited plans for a defined period (“7 days”, “30 days”). Expensive by the period but not by the GB if you use a lot of data. Not useful to me.

plans I use

The physical eSIM card I’m using has slots for 8 profiles. With the “seed” profile and the two I added below there are still 5 slots left. And depleted ones can be deleted and that slot reused.

Since my main carrier is powered by Verizon I wanted to find plans that have backends from both T-Mobile and AT&T.⁵ I assumed that Verizon would be the most expensive for them my theory was leaving that carrier out could reduce costs; see below.⁶ Why pay a premium for something I already have?

{Note: the following sections will change as I try different solutions plans.]

for emergency fallback

For fallback I picked a 10GB never-expires plan with TMO + ATT backhaul

from Roamless. Yes, ~$25 for 10GB is expensive, but it should last a long time in the emergency standby role.

for long stays in one location

For longer-term use I am looking at 30-day / 10-20GB plans with TMO + ATT backhaul from EIOTCLUB

EIOT has both TMO + ATT plans (“Double Network”) and TMO + ATT + Verizon plans (“Triple-play Network”).

	Double Network	Triple-play Network
1GB - 30 days	$5	$15
5GB - 30 days	$15	$20
15GB - 30 days	$20	$30
25GB - 30 days	$32.50	$45.50

I didn’t see any other eSIM providers that have backhaul options, but this sure looks like having fewer backhaul partners (or maybe jut not having Verizon) can bring down costs.

For my future reference some single-carrier plans with aggressive pricing on a few plans :

TMO-only providers: Mobilesim and Ubigi that have some economical 30-day plans if you pick and choose.
AT&T-only providers: MicroEsim (some plans with throttled unlimited after data used up), airhub, Esim Cards

phone

Since my main carrier is Verizon-based I wanted a different network for the phone. I am almost always on wifi except when hiking or reprovisioning so I can get by with a minimal plan. I use a $100/year AT&T MVNO for this. It’s something like 1-2GB/month plus unlimited text and calls. In actuality I use about 100MB a month on it.

previous setups

2022

camper: Cudy LTE router first with US Mobile then later with Visible. I was 100% satisfied with USM’s Verizon MVNO service but the “party plan” Visible was unlimited instead of ~22GB on USM. I don’t usually use 22GB but thought it would be nice to have in my back pocket. Visible later killed the $25 party plan but grandfathered all of is in to their basic tier for that same cost.
phone: Redpocket TMO MVNO.

2017

phone: an AT&T MVNO I can’t remember. I don’t think they exit anymore, whoever they were.
camper: I had an old Glinet wifi router that I’d tether to the phone. At various times I did it over USB, Bluetooth, etc.

frater secessus