Beryl + USB iPhone tether + Charge iphone at the same time


I bought the beryl thinking its USB 3 port would not only allow me to connect my iphone (and instantly tether) but also to charge it at decent speed at the same time.

I have discovered it cant do this.

Basically my beryl isa router in the car. I get unlimited 5g data with my carrier. The plan was to get in the car connect it to USB and away i go. With knowlege that the iphone is automatically feeding the Beryl internet but then charging it effectivly too.

I have tried a powered USB3 hub connected to the beryl and then the iphone connected to the USB3 hub, this actually works - however after a short while i get a the “trust this computer” message on the iphone looping constantly.

The reason why i’d need USB tethering is because iOS wireless tethering is unreliable and i do not want to mess around turning tethering off and on etc.

With USB tethering it just works.

Any ideas on how i could improve or work around this?


How are you powering the Beryl in the car? Make sure that the power supply is providing it with enough amps to power the Beryl and iPhone.


Using a 12v fast charger (car charger).

I have tried with the included power supply (tested in home).

It’s still the same.

Are there any configuration files that limit the power output of the blue USB A port on the Beryl?

This should not loop constantly. First time see this.

But the router is not a charger. It charegs but slow.


I’m aware it’s not intended as a charger. But the concept of getting in the car and plugging in an iPhone to a Beryl works. It’s just the charging that I wish I could improve.

Apple won’t allow wireless charging whilst also connected to a cable, so can’t do this either.

Try with a USB 3.0 Y splitter cable, which works on my GL-AR750S Slate for both tethering and charging. They are available on Amazon.

I do not work for and I am not directly associated with GL.iNet

I’ve bought one to try, thanks.

I intend to make a blog / video about this concept.

An advantage to doing it this way is

A) reliability of USB tethering
B) using the phones unlimited 5G (no extra sim contract)

WHICH splitter? Got a specific Amazon B0xxxxxx number? I’ve tried several and had no luck.

Bear in mind some downsides to phone tethering.

If the phone is left there as a hotspot device it’s possible the battery going bad won’t be noticed. I just had an S8 in a Lifeproof case give me a bit of a surprise when I opened it to discover the battery was well on it’s way to ‘spicy pillow’ stage (aka starting to bloat). Had I not been replacing it with something else we might not have noticed it until TOO LATE.

Most phones aren’t designed for 24x7 duty cycle. The heat generated from this may impact the life of the device. Some phones are worse at this than others. Check that the phone you’re hoping to use for this is up to the task.

Phone antennas are generally not as great as what you’d get from a device with an external antenna.

Some tethering gets interrupted if the phone reboots, requiring manual intervention. Which is no big deal unless you’re expecting the setup to be ‘hands off’.

Many phone plans do not support using a phone as a router. Sure, the phone is capable of it, but the carrier may decide to drop or throttle your connections if it’s detected being used for a router. It doesn’t always happen, just check how your carrier handles this before getting your hopes up.

I make these points not because using a phone this way is a bad idea, for some situations it can be pretty handy. But not all.


Tomost USB 3.0 Cable Dual Power Cables Y Adapter Type A Lead Male to Female Extension Code 30cm

In regards to the charging cycle. It wouldn’t be 24/7.

Only ever in car for an hour a day.

1 Like

Here is another one:

Grrrr just tried the cable I bought and it doesn’t offer any additional power. Waste of money.

Blue usb end plugged in to Beryl
Silver usb end plugged in to fast usb charger.

Female end plugged in to iPhone lightning cable that’s connected to my iPhone.

that’s been my experience also, several splitters don’t actually seem to pass power to the phone, and others don’t seem to pass the phone to the Slate.

I’ve seen some comments elsewhere about the voltage being an issue, and that if it’s “too low” the Slate doesn’t end up being able to pass enough to a connected device. At some point I think I changed the 12vdc-USB buck converter that’s powering the Slate, and it’s possible this replacement isn’t up to the task. But then I’m down a whole other rabbit hole finding a 12vdc-USB adjustable power supply that’ll suit the install.

It may depend on the smartphone and USB adapter. I have an Android Samsung S21+ 5G smartphone and the Y splitter cable tethers and charges with both my GL-AR750S Slate and GL-AXT1800 Slate AX.

check out 8086 consultancy on tindie… he is uk based and makes quite an array of cheap, very useful little adapters and pcbs that should be integral to all of our devices; unfortunately the pedestrian consumer isnt aware and only a small tech-dork niche need them enough to appreciate and use them…

there are uUsb and usb-c power data splitter / mergers, dual power ups/fast switching adapters, and more…

i am not paid by ^^^^^ , i am just a satisfied customer that appreciates his ability to see gaps where i see gaps and to create sensible solutions.

you could usb c power split to phone, and use 2 dual power adapters for the router and phone, running the 2d power input of each into a dual port power bank or similar configuration…

I did some checking about the voltage from the router I’ve been trying to use, a Slate. GL-AR750S Slate and power for USB tethering? - #2 by wcs2228

It seems the Slate may not be putting out enough voltage/wattage to keep a tethered phone charged.

I have not found a splitter that works either.

Thanks for updating the thread!

It’s a shame about the splitter not working.

Like I say, I had some success using a 12v powered USB hub. However there was then a continuous loop of “trust this device” messages on the iPhone.