A Penzu alternative with apps for every device
Penzu made its name as a private online journal, the kind you open in a browser and protect with a password. If that is what you want, it does the job well. But if you would also like a real app on your phone, your laptop, and your watch, with writing that works offline and a lock you can open with your face, a Penzu alternative makes sense. Purple Diary keeps the private feel and adds native apps everywhere, free and with no ads.
What Penzu is good at
Penzu is a web-first online journal built around privacy and password protection. People who want a quiet, private diary they can reach from any computer have trusted it for years, and that simplicity is part of the appeal. Mobile apps exist, and more advanced features are available on paid plans. If your writing happens mostly at a desk and a browser tab is all you need, Penzu is a reasonable home for your diary.
The trade-off with a web-first approach is the device experience. A browser tab is not the same as a native app that lives on your home screen, works offline, and opens with your fingerprint. That is the gap Purple Diary is built to fill.
Why people choose Purple Diary instead
Purple Diary is a Penzu alternative for anyone who wants the private journal and the real apps. It runs natively on iPhone, iPad, Apple Watch, Mac, Android, Wear OS, and Windows, and it still has a web app for when you only have a browser. Because the apps are native, you can write offline and your entries sync once you reconnect, so a spotty connection never stops a thought mid-sentence.
Privacy stays front and center. Instead of only a password, you get an app lock with a PIN and, on supported devices, Face ID, Touch ID, or a fingerprint. The app re-locks when you leave it. There are no ads, your data is not sold, and the content of your entries is not reused for anything beyond running the app for you.
Purple Diary vs Penzu at a glance
| Feature | Purple Diary | Penzu |
|---|---|---|
| Free to use, no ads | Yes — core journal and lock are free | Most features are part of a paid plan |
| Shows ads | No | No |
| Web app | Yes | Yes |
| Native iPhone and Android apps | Yes | Yes |
| Native Mac and Windows apps | Yes | Typically web-first |
| Smartwatch apps (Apple Watch, Wear OS) | Yes | No |
| Offline writing on device | Yes | Web journals usually need a connection |
| App lock with biometrics | Yes | Password protection |
| Mood tracking | Yes | Varies by plan |
| 10 theme colors, light and dark | Yes | A smaller set of options |
Because the exact details of another app's plans can change, the table stays general where it should. This is not about Penzu doing anything wrong. It is about matching the journal to how you actually write, and whether you want apps on every device or are happy in a browser.
A journal worth opening every day
Switching journals is only worth it if the new one is nicer to use. Purple Diary gives you a comfortable rich text editor, photo attachments and voice notes, mood tracking so you can look back and notice patterns over time, and tags that make any past entry easy to find. You can set the mood with ten light and dark theme colors, adjustable fonts and text sizes, and feed display options for how older entries appear. It is rated about 4.5 stars by more than 500 people.
If you want to keep writing in your browser, the online diary page shows how the web app fits in, and the private journal app page explains the privacy side in more detail.
Frequently asked questions
Is Purple Diary a good Penzu alternative?
It is a good fit if you like Penzu's private, password-protected approach but also want full native apps for iPhone, iPad, Mac, Android, Windows, and watch, plus offline writing and a biometric lock. Purple Diary is free with no ads, and it still offers a web app.
Does Purple Diary have native apps or just a website?
Both. Purple Diary has native apps for iPhone, iPad, Apple Watch, Mac, Android, Wear OS, and Windows, and it also has a web app you can open in any browser. Your journal syncs across all of them.
Can I write offline in Purple Diary?
Yes. Because Purple Diary has real native apps, you can write on your device without a connection, and your entries sync once you are back online.
How does Purple Diary keep my diary private?
You can set a PIN, and on supported devices unlock with Face ID, Touch ID, or a fingerprint. The app re-locks when you leave it. Purple Diary shows no ads, does not sell your data, and does not reuse the content of your entries.