This is the story of why Raj built a cold shower tracker to help people start taking cold showers - and stick with it.
(by Simon Hegener, based on the podcast conversation with Raj - full interview at the end of the article)
1. Everything Started With a Shower (Obviously)
Picture this: early morning in San Francisco.
Raj is standing under the shower while his roommates are still asleep.
There’s a small white box clipped just below the shower head.
It blinks once.
Cold water hits.
It’s this sharp but familiar feeling.
A few minutes later, he’s dry, dressed, and checking his dashboard.
How long was the cold part this time?
How cold exactly?
Did he beat yesterday?
That tiny hit of data is what keeps him coming back.
And ultimately, it’s what made him build iShiver—a device that tracks cold showers.
As he said on the podcast:
"If you're serious about your health and personal development, you can turn the knob to the left and just let the cold water run across your body." (Quote from the podcast)
2. Who is Raj?
Meet Raj:
Meet Raj: Raj lives in San Francisco and works out of Slam Spaces, a community-driven hardware incubator.
He’s one of those people who loves tracking things—sleep, food, steps, mood.
To him, “everything is better with a chart.”
His cold shower habit started in college, when he was feeling sluggish and didn’t have time for the gym.
He needed something small but effective to turn things around.
Cold showers were it.
"I used to start by taking them hot at the start and then cold for the last minute or two. And slowly, and weirdly so, I started to—this might sound dramatic—but get my life back together. Because all you need is a little change, a little bit of agency." (Quote from the podcast)
3. The Problem That Sparked the Build
Raj started by tracking his showers in a notebook.
Then in a spreadsheet.
That worked—kind of.
But it wasn’t enough to build consistency.
So he built something better.
The first version of iShiver was rough—think high school science fair.
But it tracked temperature and time.
It uploaded to a dashboard. It showed streaks.
And it worked.
Soon his roommates wanted to try it.
Then coworkers started cold showering just from hearing about it.
That’s when Raj realized this could be useful to more than just himself.
4. What He Built (and Why It’s Different)
iShiver is a small device that clips onto any standard shower pipe.
It’s battery-powered, touchless, and designed to track cold shower sessions without any setup fuss.
💡 How iShiver Works:
- Attaches to standard US shower fittings
- Tracks temperature and duration automatically
- Touchless: wave to start and stop
- Battery-powered (no plug or outlet needed)
- Data syncs to a private dashboard
- Tracks streaks to build consistency
- Multi-user support (great for households)
- Planned: social features like comparing streaks
You don’t need to open an app before your shower.
Just wave your hand and shower.
Wave again when you're done.
That’s it.
The device takes care of the rest.
"I've also been experimenting with features like total cold exposure every week, so you can kind of hit a goal without having to feel guilty about your hot showers." (Quote from the podcast)
5. The “Wow” Moment That Changed His Mind
One day at work, a few coworkers told Raj they’d started taking cold showers.
He hadn’t asked them to.
They hadn’t used his device yet.
They just heard about it—and that was enough to try.
That’s when it hit him:
It’s not about tech or tracking.
It’s about helping people show up.
If a small, simple tool can help someone take action—even once—it’s worth building.
Raj's prototype being 3d printed
6. Why This Matters
Cold showers are a habit that builds on itself. Raj admits the first few were tough, but once he started tracking them, the streak became part of the motivation.
"I think my knees are better off because I'm cold showering."
(Quote from the podcast)
He’s not trying to be extreme about it.
This isn’t about pushing to the limit or turning yourself into a biohacker.
It’s about showing up consistently—even for just 30 seconds.
7. Where He's Headed
Raj is building iShiver in public.
No secrets, no stealth mode.
His workstation at Slam Spaces is filled with 3D-printed parts, dashboards, and iterations.
His short-term goal is 1,000 preorders.
So far, he's at 7. (As Raj put it: “Hey, you’ve got to start somewhere.”)
Long-term? He wants iShiver to become the “Oura ring for your shower.”
But if it turns out that no one wants this, that's also ok.
Then he will move on to the next thing.
In Raj's words:
It’s not a business if nobody wants it.
One of Raj's big dreams is for researchers to use iShiver to study real-world cold exposure habits.
"I would love to send a university a unit—because this would be the most empirical way: using my device to test subjects." (Quote from the podcast)
8. Want To Try It?
Raj is currently inviting testers and looking for a marketing co-pilot to help bring iShiver to a broader audience.
If you want to support, collaborate, or just geek out about cold exposure tracking:
9. Final Thoughts
Raj’s approach is refreshingly simple:
Start small.
Don’t overthink it.
Cold doesn’t have to be extreme to be effective.
You don’t need to post it on Instagram or last 10 minutes under freezing water.
Just start.
Finish your warm shower with 15 seconds of cold.
Then see what happens.
And if a little white box helps you stick with it?
Cool. (no pun intended. maybe)
Full Podcast Episode
Enjoy!
Please let me know who you would like to have on the podcast next.
Send me your recommendations to info@enterthecold.com.
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