For most US buyers the answer is the hotspot, and the reason is not cost. A 4G AI Box is only as good as its band list, and a box that does not publish which LTE bands it supports may show no signal at all on a US carrier. Until a seller states the bands, the hotspot version is the only one you can be sure will work, and it is the cheaper one. Here is what each needs to be true, what an hour of video costs on each, and the one question to ask before buying a SIM version.
| Phone hotspot | SIM in the box | |
|---|---|---|
| What has to be true | Your plan allows hotspot data | The box's LTE bands match your carrier |
| Data cost per HD hour | Up to 3 GB from your phone plan | Up to 3 GB from a second line |
| Speed and reliability | Depends on phone signal and band | Depends on the box's modem and bands |
| Battery and friction | Phone battery; hotspot on each trip | Box comes online by itself |
| Pick it if | You want it to work today | The seller has published the bands and you want the phone out of it |
What each one needs to be true
An AI Box streams from the internet, and it gets the internet one of three ways. As one troubleshooting guide lists them, "Wi-Fi, tethering, and, on some models, built-in 4G/5G data". In a moving car Wi-Fi is not an option, so the choice is between tethering to your phone's Personal Hotspot and a SIM card inside the box.
The hotspot needs one thing: a phone plan that allows hotspot use, which most US plans do with a monthly allowance. The SIM version needs two: a plan on a second line, and a modem inside the box that speaks the frequency bands your carrier uses. The first is a phone-bill question. The second is a hardware question, and it is where SIM boxes go wrong.
Data: what an hour of video costs on either
The data is the same either way; only the bill it lands on changes. Netflix's own figures per hour are up to 1 GB at standard definition and up to 3 GB at high definition; the low setting is up to 0.3 GB. A 40-minute episode in HD is therefore around 2 GB. On a hotspot that comes out of your phone plan's hotspot allowance; on a SIM it comes out of whatever plan is on the second line.
What differs is what happens when the allowance runs out. Many US plans slow hotspot traffic after a monthly cap rather than cutting it off, which on a box shows up as a picture that drops to low quality mid-episode. A dedicated line has its own cap and its own rules. Neither is free; the hotspot is only free if you were already paying for hotspot data you do not use.
The band question
This is the part that decides it, and it is the part product listings leave out. LTE is not one network; it is a set of frequency bands, and a modem supports some of them and not others. The bands US carriers rely on include Band 2, 4, 12 and 66 on AT&T and T-Mobile, with Band 13 important on Verizon; your carrier's own coverage pages list the bands that apply to your plan. A modem built for another market can support a completely different set, be a perfectly good modem, and see nothing in Texas.
So the question to ask any seller of a 4G AI Box is exact: which LTE bands does the module support? Not "does it work in the US", which invites a yes; the list. If the list includes the bands above, the SIM version will work on those carriers. If the seller cannot produce a list, assume it will not, and buy the hotspot version.
Speed, battery, friction
A hotspot is as fast as your phone's signal and as reliable as your phone's battery. Two practical points. First, an iPhone's Personal Hotspot broadcasts on 5 GHz by default; if the box only sees 2.4 GHz, iPhone settings have a toggle for it. When Apple added the 5 GHz hotspot, the same setting added a "Maximize Compatibility" toggle "that reverts Personal Hotspot to 2.4GHz Wi-Fi when enabled, with Apple noting that this may reduce internet performance on devices that are connected to the hotspot." That is the trade: compatibility for speed. Second, the hotspot is one more thing to turn on when you get in the car, and one more thing draining the phone while you sit parked.
A SIM box comes online by itself when the car starts and leaves the phone out of it. That is its real advantage, and for someone who uses the box daily it is a real one. It is also the only reason to accept a second line and the band research.
What it costs
We are not going to quote carrier prices; they change monthly and vary by plan. The shape of the cost is this. Hotspot: nothing extra if your plan's hotspot allowance covers your viewing, and a plan upgrade if it does not. SIM: a second line, every month, whether you drive or not, plus the box's higher price. For a passenger who watches a show on a road trip twice a month, the hotspot wins by a distance. For a daily rideshare driver whose passengers stream for hours, a dedicated line can pay for itself in convenience.
| Criterion | Phone hotspot | SIM in the box |
|---|---|---|
| What has to be true | Plan allows hotspot data | Box's LTE bands match your carrier; second line |
| Data per HD hour | Up to 3 GB (Netflix figure) from the phone plan | Up to 3 GB from the second line |
| Speed and reliability | Phone signal; 5 GHz by default, 2.4 GHz optional | Box modem; only as good as its bands |
| Battery and friction | Phone drains; hotspot on each trip | Online by itself |
| Pick it if | Occasional viewing; you want certainty | Daily heavy use and a published band list |
Questions we get
Does the Cabinory AI Box have a SIM slot?
The version we sell does not; it uses your phone's hotspot or Wi-Fi.
Will you sell a 4G version?
A 4G version of the same box exists at the factory, and we have asked for its LTE band list. We will list it only when we can publish that list on the product page, so that a buyer on AT&T, T-Mobile or Verizon can check it against their carrier before ordering. We do not sell the 4G version yet, and we would rather not sell it than sell it without the bands.
How much hotspot data does an AI Box use?
The same as the app would use on a phone: by Netflix's figures, up to 1 GB an hour at standard definition and up to 3 GB at HD.
Why does my box not see my iPhone hotspot?
Often because the hotspot is on 5 GHz; turn on "Maximize Compatibility" in Personal Hotspot settings, which moves it to 2.4 GHz.
Before you order
If you want the box to work this week, buy the hotspot version and turn on the hotspot when you park. If you want a SIM version from anyone, get the band list first. Ours will have one on the page or it will not be on the page. The AI Box we sell today is the hotspot version; ask us if your plan's hotspot rules make you unsure.
One-page answers to the questions this piece raises: does-cabinory-ai-box-have-sim-slot.