Hi, interesting question. I think that not all the dry-erase marker work in the same way. I used my Double Cross 10 times maybe and now it doesn't write anymore because the cartridge is dry.
So, I like this trick, but I used very rarely. I can't spend $25 everytime for a refill if it happens so often.
I'll appreciate any suggestion.

I found 2 ways to revive it, now I have to try.
Meanwhile, I share what I found

Method 1:

Wikipedia had an awesome simple trick that really works!

-Take long piece of string or yarn ,about 2ft. in length, and tie one end around your marker towards the back end.
* make sure to tape it down so the marker won't fly off and it something or somebody.
* also make sure the marker cap is on securely as this could cause ink to splatter if it's not.
– Then hold it above your head and swing it around like a lasso for about 1 to 2 minutes.
– Then take off the cap and write.

Method 2:

Refilling via syringe the cartridge with Whiteboard/Dry Erase Board Liquid Cleaner that is Isopropyl Alcohol, the same liquid that is inside the marker at the beginning.
If anyone do that... be careful!

If you have other ideas, please share
Bye.

Michele

Here is my review of Double Cross.

Highly recommend double cross with overlayed app. Great way to incorporate the phone and photos.

I am patiently waiting to have enough money to order this Double Cross Holder from The Mind Hacker. This solves the problems I've had with Double Cross and this item will likely bring DC back into my performing rotation.

If you are not utilizing double cross with the overlayed app you are missing out!

A quick search didn't reveal much. Can you provide a link?

Quick google came up with this for Overlayed

https://apps.apple.com/us/app/overlayed/id1662541756