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Project Euler is a series of challenging mathematical/computer programming problems that will...

Veklar
Sociall (Beta)
Habitica
Solcial
Karmanadi
Habitify
ChatterBooth
A habit tracker that can't read your habits.

Which is more popular?
Based on our record, Project Euler seems to be a lot more popular than Metamorphic. While we know about 415 links to Project Euler, we've tracked only 1 mention of Metamorphic.
Website, pricing, platforms and company facts side by side.
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| Website | projecteuler.net | metamorphic.app |
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| Company | — | Startup from the United States · 1 - 9 employees · 2026 |
| Listed in |
In their own words, as submitted to SaaSHub.


No description of Project Euler yet.
The zero-knowledge habit tracker that puts you in control. End-to-end encrypted, beautifully simple, and built for people who take their privacy — and their progress — seriously.
What each product offers, as listed by its team.


Possible disadvantages
An editorial look at what each product does well and who it suits.


Overall verdict
Why this product is good
Recommended for
No analysis of Metamorphic yet.
Walkthroughs and reviews on video.
Project Euler Challenges 1–4 - Coding Challenges with Florin
More videos
Creator Walkthrough: Exploring Metamorphic’s Features & Benefits
How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing Project Euler and Metamorphic.
Metamorphic's answer:
Metamorphic is a new product and we don't disclose customer names. By design, we know as little about our users as possible — that's the point of zero-knowledge architecture.
Metamorphic's answer:
Metamorphic is a zero-knowledge, end-to-end encrypted habit tracker — every piece of user data is encrypted client-side before it ever reaches the server. Unlike competitors that treat encryption as a premium add-on, Metamorphic includes it on every plan, including Free. It also uses hybrid post-quantum cryptography (ML-KEM-768 + X25519), the same approach adopted by Signal and Apple iMessage, making it one of the first habit trackers with quantum-resistant key distribution. The server never stores plaintext — not even your email address.
Metamorphic's answer:
Most habit trackers store your data in plaintext on their servers. Metamorphic never sees your data — all encryption and decryption happens in your browser. If the server were fully compromised, an attacker would get only opaque ciphertext. Beyond privacy, Metamorphic is a complete self-improvement platform: habit tracking with streaks and drag-and-drop reordering, goal setting with milestones and progress bars, daily self-reflections with mood tracking, a full schedule and calendar with recurring events and printable views, progress insights with activity heatmaps, and family/group accountability with shared habits and goals. You get the depth of a full-featured tracker with the privacy of an E2E encrypted system — no trade-off required.
Metamorphic's answer:
Privacy-conscious individuals and families who want a serious habit and self-improvement tool without surrendering their personal data to a third party. People who care about building better routines — daily habits, long-term goals, journaling, scheduling — but also care about who can read their data. Particularly relevant for anyone who has thought twice about logging personal struggles, health habits, or family goals into an app that stores everything in plaintext.
Metamorphic's answer:
Metamorphic grew out of a personal conviction. Its creator, Mark Thayer, was building another app (Mosslet) around the time he was becoming a new dad. Reading Shoshana Zuboff's The Age of Surveillance Capitalism made him want a better digital world for his child. When Meta rolled back end-to-end encryption on its direct messaging, he was pushed to implement real E2EE in Mosslet — built on an asymmetric, password-derived key architecture.
The idea for Metamorphic itself came from his partner, who is passionate about psychology and behavior — always thinking about how to break old habits and form better ones. It clicked: something as personal as your habits, goals, and daily reflections should be private to only you, and you shouldn't have to worry about it being otherwise. So Metamorphic was built from day one around zero-knowledge architecture, where encryption is the foundation rather than an afterthought.
Metamorphic's answer:
Share your experience with using Project Euler and Metamorphic. For example, how are they different and which one is better?
External articles and on-site reviews we used to compare the two products.


Project Euler provides a large collection of challenges in the domain of computer science and mathematics. The challenges typically involve writing a small program to figure out the solution to a clever mathematical...
If you are studying algorithms and computer programming, chances are you’ve heard of Project Euler. A collection of mathematical problems made for problem solvers who are interested to combine mathematics and...
We have no reviews of Metamorphic yet. Be the first one to post
Recommendations tracked on public social media and blogs since March 2021.


Let's hope this is going to help me solve some more Project Euler [1] problems! [1] https://projecteuler.net/. - Source: Hacker News / 4 months ago
Https://projecteuler.net/ for "Thinker" brain food. (it still has the issue of not being a pragmatic use of time, but there are plenty interesting enough questions which it at least helps). - Source: Hacker News / 7 months ago
I have a Project Euler (https://projecteuler.net/) account. Though I do not register at all on the leader board I will sometimes work obsessively on a problem just to make one of the level icons light up for me. There is not really... - Source: Hacker News / 9 months ago
I'm the solo dev at Moss Piglet, a bootstrapped public benefit company. I've been building Metamorphic — a habit and self-improvement tracker where all personal data is encrypted client-side before it ever reaches the server. The server... - Source: dev.to / 5 months ago
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