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Whistle 2026.2 is here

We make software
we're proud of

A tiny studio with unreasonable standards. We make our own apps, design brands, and build software for people who notice the difference.

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We are nerds.

We build for awe, not engagement. For moments of clarity, not hours of scrolling. We want our apps to make your day a little better.

We believe your data is yours. It stays on your device, not our servers. We don't track you. We don't sell you. We don't even want to know who you are. We just want to make something useful for you.

We build software that lasts. No subscriptions that hold your data hostage. No growth hacks that prioritize metrics over people.

We optimize for stories, not profit. For the person who tells a friend, not the metric that impresses investors. We'd rather have a thousand people who love what we make than a million who feel trapped by it.

We're small on purpose. No investors. No growth targets. No trend chasing. Just two friends building software we'd want to use. That's it. That's the company.

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Florian

Clemens's signature

Clemens

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These are ours

These are the apps we build for ourselves, tools we use every day to sleep better,
train smarter, and feel more energized.

Trusted by thousands

We build for people who notice the details. Turns out, they write reviews too.

New Apps We LoveApp Store
This Week’s FavoritesApp Store
Top 10 Finance AppsApp Store
  • I don’t normally review or rate apps, so my willingness to do so is a testament to the app. This app has a simple purpose - present information about my sleep and energy levels to me in a way that I can understand. Goal Achieved. In addition the app has a simple, clean UI that does it’s job.

    App Store Review

  • Peaks is a must have companion app to help you understand the benefits of sleep with your life. Has great information, as well as, information that helps plan your day to be more productive! Download and give it a try!

    App Store Review

  • Perfect companion to make most of my time by helping me adjust types of work to specific cycle in my circadian rhythm. I know when to deep focus, I get nudge when to rest and take it easy. My life is so much more comfortable with this app!

    App Store Review

  • This app is exactly what I was looking for all the insights I need with simplicity and flexibility

    App Store Review

  • I was curious about my energy ups and downs and this app really has helped me think more about when to focus, exercise, and just take a break.

    App Store Review

  • I love Macaw. I wanted a simple budget tracking app with enough complexity to keep track of multiple buckets and enough simplicity to not require a PhD to set up those buckets and track the expenses taken from them.

    App Store Review

  • I’ve been using this app for years at this point and it predicts my rhythm and helps me better understand my energy levels and body

    App Store Review

  • This is an outstanding app that's hard to find anything similar among its peers, can be considered a semi-exclusive software, and this latest update is particularly impressive.

    App Store Review

  • This app is beautifully designed, and very easy to access the information I’m looking for at a quick glance. It’s also very customizable as to what information you actually want to see. Overall amazing app!

    App Store Review

The messy middle

Building software is full of wrong turns and hard calls. Here's what that actually looks like.