BeltDrivenEnder3 VS AndroidKlipperScreen

Or you can go for "belted Z" that is available on github by kevinakasam. https://github.com/kevinakasam/BeltDrivenEnder3

This is called Z banding which happens on ender 3 style printers with a single Z rod, you can buy a dual Z axis kit but I would recommend Belted Ender 3 mod instead as it will almost remove it completely and is around the same price, more DIY though.

After that, convert your printer to belt driven. The kit's only $25 and easily the best upgrade you could do on that unit. That link has some example prints, all the .stls, and links where you can get the kit

There are also more radical approaches. KevinAkaSam has a mod that foregoes leadscrews altogether, using a system of belts to drive the Z-axis instead. This is still a Cartesian printer, but since there are no leadscrews, there is no leadscrew wobble. It still uses only one motor (like the belted-leadscrew approach above, though it moves that motor to the top of the printer, so you might need a longer cable for it.

Tbh, I think it's more trouble than it's worth. There are several ways to get dual z without dual steppers, and it's less effort that way. My preferred dual z solution is a belted z axis like kevinakasam's mod. https://github.com/kevinakasam/BeltDrivenEnder3

If you are doing this Ender3 mod, then the settings stay the same.

On my V2, once I finished all the pieces for the belted Z mod, I used the old extruder motor to replace the Z axis motor since is is a bit stronger.

You can feel this if you carefully manually turn the lead screw. You will feel more resistance at some points. There are some simple fixes that you can find on reddit for adjusting the bracket. You can also replace that bracket by going to a belt drive. https://github.com/kevinakasam/BeltDrivenEnder3

Try this. I found it was helpful for installing klipper screen on android. https://github.com/naruhaxor/AndroidKlipperScreen. You will also probably want to install Google Play on your kindle first so you can install XSDL. https://www.howtogeek.com/232726/how-to-install-the-google-play-store-on-your-amazon-fire-tablet/. I tried sideloading XSDL on my kindle without the google store, but couldn’t get it to work. When in installed google play, then downloaded the latest XSDL from the Google Store, it worked without an issue.

That's just an old android phone, using KlipperScreen

Here's a guide on how to do it

KlipperScreen on Android

How to install KlipperScreen on an android device: https://github.com/naruhaxor/AndroidKlipperScreen