A private notes app for Android, and what each one protects

The right private notes app for Android depends on who you want to keep out. If your notes must reach other devices, choose one that encrypts them end to end, such as Standard Notes or Notesnook. If they can stay on one phone, TackNote for Android is a sticky notes app that keeps every note encrypted on the phone, with no account, and can put any note behind your screen lock.

We make TackNote, so we have tried to be fair to the others and plain about where ours falls short. Three questions below point you to a pick, and every answer it gives is also written out in Which one fits you.

What "private" can mean in a notes app

The word covers three different protections, and an app can be strong on one and silent on another.

• The company and its servers. With end-to-end encryption, the maker holds your notes but says it cannot read them. An app with no server for your notes never receives them at all.
• Someone holding your phone. A lock on a note keeps it shut when you hand the phone to a friend or a child.
• The screens around the app. A note can still show up in a notification, a widget or the app switcher. Check these as well if the note holds a door code.

Google Keep

Keep ties your notes to your Google Account. Google says what you save is private to you unless you share it, that data is encrypted in transit and at rest, and that Keep does not use your information for advertising. It also says it accesses private content only with your permission or when required by law, and that Keep processes your content for features such as handwriting recognition (Google Keep Help). That page does not mention end-to-end encryption.

For shopping lists and everyday notes that should stay out of ads and out of strangers' hands, Keep is a sensible choice, and it syncs across your devices.

Samsung Notes, on Galaxy phones

Samsung Notes can lock a note with a password you create, and a Samsung account is required to lock notes. Samsung Cloud can sync your notes across your other Galaxy devices (Samsung Support).

If you own a Galaxy and mostly want a lock against people nearby, try this first. It is already there.

Standard Notes

Standard Notes describes its end-to-end encryption as audited and says only you have the keys that decrypt your data (Standard Notes). The free plan includes that encryption, plain text notes, sync across unlimited devices and password-protected notes. Paid plans are listed at $90 and $120 a year (plans). It can also run offline without an account, and then you set an application passcode to keep encryption active (Standard Notes Help). It is on Google Play.

If your notes are mostly text and must sync with strong encryption, start here.

Notesnook

Notesnook calls itself an open source, zero knowledge notes app, and it runs on Android, iOS, Windows, macOS, Linux and the web. A vault adds a second password for your most private notes (Notesnook). The free plan has unlimited notes and 50 MB of attachment storage a month, and its table lists app lock as a paid feature (pricing). Because of the encryption, Notesnook says it cannot restore your data if you lose both your password and your recovery key (Notesnook Help).

It is a good fit if you want encrypted sync across phones and computers, plus a second password on your most private notes.

Joplin

Joplin is free and open source, runs on Android, and is offline first, so all your data is on your phone. It can sync through services you may already use, including Nextcloud, Dropbox and OneDrive, as well as Joplin Cloud (Joplin). End-to-end encryption is off until you turn it on, and its password cannot be recovered (Joplin Help).

If you like to choose where your notes sync, or want code you can read, this is the one. Turn encryption on when you set up sync.

TackNote for Android

TackNote takes a different route: there is no account and no server for your notes, and a note can hold a recording, photos and a checklist as well as text. Here is what that covers.

• No account. Open the app and start. There is nothing to sign up for, and your notes are never sent to us.
• Encrypted on the phone. Notes, pictures, videos and recordings are sealed with AES-GCM under a 256-bit key.
• Private notes behind your screen lock. Tap the lock on a note and it opens only with your fingerprint, PIN, pattern or password. It locks again when you leave TackNote.
• Hidden on the screens around it. A locked note shows "Private note. Unlock to read." on the board and in search. Reminders and place alerts never show its words, and a widget shows only its color and a lock.
• No peeking at the screen. The app switcher never gets a picture of TackNote, and screenshots are blocked while a private note could be on screen unlocked.
• Words written on the phone. Transcripts, speaker labels and summaries are worked out on the device. Our guide to recording and transcribing a meeting on Android covers that part.
• Backups go where you choose. They are off until you turn them on, and they are sealed with a passphrase of at least 8 characters before they reach the folder or files you pick. Android's own Google backup includes TackNote only when that backup is end-to-end encrypted with your screen lock.
• What goes online. Your Google Play purchase, the map tiles on the Where written map, and getting Google's on-device summary model ready. None of these receive your notes.

The six side by side

Where TackNote falls short

• A private note is a lock, not a second password. It controls what TackNote shows. Anyone who knows your phone's PIN can open it. Notesnook's vault uses a second password of its own.
• You need a screen lock. TackNote will not make a note private on a phone without one, because you could never open it again.
• No sync. TackNote for Android does not sync with other devices or with TackNote for Mac or Windows. Our guide to sticky notes apps for Android covers the apps that do.
• Our code is not public. Joplin and Notesnook describe themselves as open source. With TackNote you are relying on what we say here.
• A recording in progress. The short segment being written is unencrypted on the phone until that segment closes, then it is sealed.
• What you send is out of our hands. A .tacknote file is not encrypted, so send it the way you would send any private document.
• A lost passphrase is lost. We cannot recover a backup passphrase, because we never have it.
• It needs Android 13 or later, and it is not free forever. After the 7 days your notes stay readable, searchable and shareable, and $24.99 once lets you make and change notes again. No subscription.

Which one fits you

• Your phone is older than Android 13: TackNote will not run on it. Look at Standard Notes or Joplin, and check each Google Play listing, because we did not confirm which Android versions they support.
• Your notes must sync, encrypted, across your devices: use Standard Notes or Notesnook.
• You want to sync through a service you already have: use Joplin, and turn on its encryption.
• You only need to reach other Galaxy devices: use Samsung Notes with Samsung Cloud.
• The phone is enough, and your notes hold recordings, photos or lists: use TackNote for Android.
• The phone is enough, and you want text in a free, open source app: use Joplin.
• These are everyday notes that just need to stay out of ads: Google Keep does this well.

Common questions

Is Google Keep private?

Google says what you save in Keep is private to you unless you share it, that data is encrypted in transit and at rest, and that Keep does not use your information for advertising. Its help page on the subject does not mention end-to-end encryption.

Which private notes apps for Android work without an account?

TackNote for Android has no account at all. Standard Notes says it can be used offline without an account, and it asks you to set an application passcode to keep encryption active.

Can you lock a single note on Android?

Yes, in several apps. TackNote uses your phone's screen lock. Samsung Notes uses a password and needs a Samsung account. Standard Notes includes password-protected notes on its free plan, and Notesnook has a vault with a second password.

Does TackNote for Android sync private notes?

No. TackNote for Android does not sync with other devices. You can keep a backup, sealed with your passphrase, in a folder or files you choose.

What happens when the TackNote trial ends?

Everything works free for 7 days. After that your notes stay readable, searchable and shareable, and one payment of $24.99 on Google Play lets you make and change notes again. No subscription.