The Ndless Team devotes itself to open your TI-Nspire to the greatest community programs, OS update after OS update since 2009. We have once again reopened the door for OS versions 3.9.0 and 3.9.1. TI-Nspires sold with pre-built OS 3.9.1 (HW-S) can now enjoy the sweet taste.
If you already have Ndless 3.6 for OS 3.6 installed, stick to it as OS 3.9 doesn’t offer much interesting, and Ndless 3.9 re-installation after reboot is computer-dependent.
Owners of HW-S, grab your can on ndless.me!
ndlessly 
That is awesome!! I finally can use Ndless on my new TI-Nspire CX CAS!!! Thx!!
Can someone elaborate on this “Ndless 3.9 re-installation after reboot is computer-dependent.”?
If you reboot the calculator, you need to attach/unattach a usb cable for the OS to allow ndless to be installed again. Doesn’t actually matter what the cable is connected to as long as it has power. If you downgrade to OS 9.6, the calculator will shut off if it’s not connected to a power supply. That also doesn’t fix the reboot thing. PLEASE PLEASE FIX THIS! I’d like to overclock my calculator please.
Look up a program called nlaunch, it should let you downgrade your calc without causing problems.
You can also use it to upgrade up to 3.9 again if you so desire.
I’m running into the same problem. The overclocking app reboots the calculator which takes away ndless every time
You need to set the frequency of nover lower until it doesn’t reboot.
Theoretically if you manage your battery right and don’t install unstable apps you’ll never need to reboot your calc.
Well apparently I have ti nspire cx and i screwed up, resulting in 4.0 OS installed on my handheld. Any tips on how i can install ndless on that? Downgrade?
Ndless is currently not compatible with OS 4.0 :( Please see the latest post: https://ndlessly.wordpress.com/2015/05/17/os-4-0-please-wait/
Just a quick question: Why exactly is nothing compatible with the monochrome touchpad CAS nSpire? I just bought one and upgraded it to 3.9 without thinking about it and now it seems like i’m stuck. Any options??
It’s actually for an unknown reason, it simply doesn’t work…
You can reflash boot2 1.4 and use nLaunch: https://github.com/Excale/nLaunchy
Okay, I’ve looked over everything and am still stuck. Just how do I do that? I don’t want to sound like a noob but the nLaunchy tutorial is no help, it just says “do this” as if I’m expected to know how to do that. I have OS 3.9.0.463 and cannot figure out how to install boot2 1.4. Is there any chance of DowngradeFix 3.9 being compatible with the touchpad in the future?
I just got my cx cas today pre-installed with 3.9.1 so does it mean when you say, “Ndless 3.9 re-installation after reboot is computer-dependent” that I can only use ndless when a computer is connected?
Nick: this means you can only install Ndless connected to a computer. You can of course use it without a computer. Note that some programs may reboot the calculator on crash.