If you searched "Diary with Lock vs Mann", you probably have one question: where do I put the thing I cannot say to anyone, so that nobody in the house finds it. Diary with Lock, by Simple Design Ltd., has more than a crore of installs on Google Play, per its Play listing. It is a diary with a PIN in front of it. Mann is a journal that writes back. They are not the same kind of app.
We make Mann, so read this knowing that. Diary with Lock does several things Mann does not, and we list every one of them.
Everything about Diary with Lock here comes from its Google Play India listing, its data safety page, and the privacy policy the listing links to, read on 9 September 2026. Links at the bottom. It has no AI, so we do not compare AI. We compare a lock to encryption, and a diary to a journal that says something back.
The short answer
Pick Mann if what you write is heavy enough that you want it encrypted before it is stored, and you want one sentence said back after you save, in Hindi, Hinglish, Tamil, Telugu, Kannada, Bengali, Marathi or English.
Pick Diary with Lock if you want a free diary with a lock on the front, pictures, fonts and themes inside, a backup you can restore on your next phone, and you do not mind ads.
Price, side by side
| Diary with Lock | Mann | |
|---|---|---|
| Free plan | Free. The Play listing carries the "Contains ads" badge. | Free, no expiry. Unlimited entries, one AI reflection a day, 10 chat messages a week. |
| Monthly | Not stated on the Play listing. The listing shows in-app purchases from ₹95 to ₹3,850 per item, and does not say what each one buys. | ₹199 |
| Yearly | Not stated on the Play listing. | ₹1,699 |
| Ads | Yes. The privacy policy names AdMob by Google for personalised ads, and says you "may still see ads" after opting out of personalisation. | None. |
Feature by feature
| Diary with Lock | Mann | |
|---|---|---|
| What happens when you write | The entry is saved. Nothing reads it and nothing replies. | Mann says back the one thing in your entry that carried the most weight, then stops. No advice, no question. |
| Languages | Not stated on the Play listing or in the privacy policy. | Writes back in 8 Indian languages: English, Hindi, Hinglish, Marathi, Bengali, Tamil, Telugu, Kannada. The app's own screens are in Hindi, Hinglish and English. |
| What it costs in India | Free, with ads. In-app purchases run ₹95 to ₹3,850 per item; the listing does not say what each one buys. | Free, no expiry. Premium ₹199 a month or ₹1,699 a year. |
| Where your words go | The privacy policy: "your diary data is only stored locally on your device unless you actively login and backup" to your Google Drive. It does not mention encryption of the diary. Play's data safety page: encrypted in transit; may collect device IDs, optional name and email, crash logs, app interactions; no data shared with third parties. | Entries are encrypted on your phone before they are stored. Mann's servers hold ciphertext. Your words are read in flight, not at rest: a private safety screen reads every finished entry once, even one that gets no reflection, and the AI (Google Gemini) reads it when it writes your reflection. Nothing is kept. |
| Crisis | Neither listing describes anything similar. | If an entry reads to Mann like a crisis, Mann gives helplines instead of a reflection: iCall 9152987821, Vandrevala Foundation 1860-2662-345. |
| Made for | A global audience. Simple Design Ltd., with a Hong Kong address in the Play contact block. | India. Joint families, career pressure, the rishta conversation, log kya kahenge. A small team in Pune. |
| Chat | None. | A separate "Talk to Mann" chat. 10 messages a week free, unlimited on Premium, within a fair-use budget of 200 AI calls a day. Chat messages are not encrypted yet. |
| Memory across entries | None. Search by date, keyword, picture or tag. | Split. The reflection you get after saving is written from that entry alone, with no history. Memory shows up elsewhere: chat, the opening prompt and the weekly report draw on the opening of your recent entries and up to ten open threads Mann is still holding. Threads expire after 30 days and you can delete any of them. |
| Voice | Not stated on the Play listing. | Voice journaling on Premium. |
| The lock | Pattern, digit PIN or fingerprint, with a password hint. Forget it and the listing says you can retrieve it "via verified email". | An app lock that uses your phone's fingerprint or face unlock. No PIN fallback, and it unlocks automatically if biometrics are removed from the phone, so it stops casual access, not a determined one. |
| Mood and insights | A mood on each entry and a calendar view of it. | A weekly report from your real week: mood, days written, word counts, the people you mentioned. Full version on Premium. |
| Pictures, fonts, themes | Yes, all of them. | Text, and voice on Premium. No pictures, fonts or themes. |
| Platforms and a new phone | Android, on phone, tablet and Chromebook. Back up to Google Drive, restore on your next phone. | Android and iOS. Entries cannot be opened on a second phone, because the key never leaves the first one. No web app. |
Where Mann is better
What is done to the words before they are stored. Diary with Lock puts a lock in front of the diary. Its privacy policy says the diary lives on your phone, and on your Google Drive if you back up, and does not mention encrypting the diary itself. Mann encrypts every entry on your phone before it is stored, so Mann's servers hold ciphertext. A lock stops the person holding your phone. Encryption changes what the words look like wherever they sit.
Something writes back. In Diary with Lock you write and the page stays quiet, which is what a diary is. In Mann you save and one sentence comes back: the thing you buried in paragraph four. If you have ever written three pages and still not known what was bothering you, that is why Mann exists.
Hindi, Hinglish and the rest. Mann writes back in eight Indian languages and was tuned for Hinglish, not translated into it. Diary with Lock's listing does not say which languages it supports.
No ads. The place you write the thing you cannot say should not also be selling you something.
Where Diary with Lock is better
Price, if you never pay. The diary, the lock, the mood calendar and the pictures are all in the free app. You pay with ads. In Mann, unlimited reflections and chat are ₹199 a month.
Your next phone. Diary with Lock backs up to your Google Drive and restores on a new phone. Mann's key never leaves the phone it was made on, so your entries stay there. Lose that phone and they are gone. If you want the old years on the next phone, Diary with Lock does that and Mann does not.
Pictures and decoration. Photos, fonts, backgrounds, themes. Mann is a text box and, on Premium, a microphone. If your diary is also a scrapbook, this is not close.
Who each is for
Mann is for someone with nobody safe to tell. You write the thing, in whatever language it arrives in. It is encrypted on your phone before it is stored. Mann says back the sentence carrying the most weight, and gets out of the way. It is free, it stays free, and Premium is ₹199 a month.
For most people reading this in India, Mann is the one to start with. It is free, it is in your language, and it costs ₹199 if you ever pay.
Diary with Lock is for someone who wants a diary, with a lock, on a phone, for free. It keeps the writing behind a PIN, holds your photos, and follows you to your next phone. If a locked diary is the whole ask, it is a good answer.
Questions people ask
Is Diary with Lock available in India? Yes, on Google Play India, with in-app purchases priced in rupees. An App Store India app with the same name and a similar bundle id is published as "Simple Health". Neither listing says the two are the same company, so this page covers the Android app.
Does Diary with Lock support Hindi? Not stated on its Play listing or in its privacy policy. Mann replies in 8 Indian languages, Hindi and Hinglish among them.
Which is cheaper? Diary with Lock, if you use the free app and accept the ads. Its in-app purchases run from ₹95 to ₹3,850 per item and the listing does not say what they buy, so paid against paid cannot be compared. Mann Premium is ₹199 a month or ₹1,699 a year.
Can I move from Diary with Lock to Mann? Its Play listing does not mention an export. Mann has no import today. You would start fresh, which for a journal is sometimes the point.
If that is what you were looking for
Writing in Mann is free, as much as you like, with one AI reflection a day and 10 chat messages a week. Premium is ₹199 a month or ₹1,699 a year. Get Mann here.
Or don't. A paper notebook does most of this, and we say that on every page. A notebook with a lock is a diary. Neither can say back the sentence you buried in paragraph four.
Still deciding? This page is one of thirty. The whole set, with prices in rupees and the rows each app wins, is in Best AI journaling apps in India.
Checked on 9 September 2026 against the Google Play India listing, its data safety page, the Simple Design privacy policy (last updated 15 December 2023), and the App Store India listing published as Simple Health. If Diary with Lock changes something and we have not caught up, write to support@mannjournal.app and we will fix the page.
Want to start journaling tonight?
Mann is free to download. Unlimited journaling, no credit card.
