Nsila privacy policy

1Who is responsible

Nsila is built and published by Abdul-Qudus Rufai, an independent developer based in Nigeria. For anything covered by this policy, Abdul-Qudus Rufai is the data controller.

Contact: info@rufixduke.ng

2The short version

There are no accounts, no ads and no analytics or tracking tools in the app.
The camera is read on your phone. No video, photos or landmarks are sent anywhere by the app.
Practice results, settings and recordings are stored only on your phone.
Recordings leave your phone only if you choose to share a file yourself.
The one thing the app downloads is a public word list from this website. That request carries nothing about you.

3Camera and on-device processing

Nsila needs the camera to see your hands. Each frame is read on the phone by an on-device hand tracking model (MediaPipe), turned into a set of landmark points, and then thrown away. Frames are never saved as photos or video and are never uploaded.

For letters, the app tracks 21 points on one hand. For word signs, it also tracks both hands and a few upper body points (shoulders, nose and wrists) so it can tell where your hands are relative to your body. These points are used to recognise the sign. They are not used to identify you, and the app does no face recognition.

You can turn off camera access at any time in your phone’s settings. The app can’t recognise signs without it.

4What is stored on your phone

The app keeps the following in its own private storage on your device:

Your settings, such as theme, which hand you sign with, speech, haptics and reminder time.
Practice progress: which letters you have practised, results and your streak.
My words: the words you type in and the landmark recordings you make for them.
Contribution recordings, if you opt in: hand landmarks per frame and which hand you used, plus the time you gave consent.
A cached copy of the public community word list.

None of this is sent to me or to anyone else by the app. Recordings are kept out of cloud backups and device-to-device transfers, so they stay on the phone they were made on.

5What is not collected

No name, email address, phone number or account details. The app has no sign-in.
No photos, video or audio.
No location.
No advertising ID or device ID.
No usage analytics or crash reporting tools.

Nsila gets better when more people’s signing is included. Two features let you help, and both are off until you choose to use them.

Contribute hand data

After you read and accept the consent screen, you can record letters the app finds hard. Only hand landmarks are saved. When you tap Share recordings, the app makes one file and opens your phone’s share sheet. You decide where it goes, for example an email to info@rufixduke.ng.

Contribute words

You can share word signs you have recorded in My words. The file contains the hand and body landmark movements for those words, the words themselves, which hand you sign with, the app version, the date and a random contribution ID.

What a shared file never contains

Photos, video, your name, contact details or a device ID. If you send the file by email, your email address and anything you write in the message will reach me the same way any email would.

How shared recordings are used

Only to improve sign recognition in this free, non-commercial app. Shared word signs are checked by Deaf NSL signers, and a word becomes available to everyone once enough people have recorded it. The published community list contains words and recognition data built from many people’s recordings. It does not list contributors.

Contributions are collected with your explicit consent under the Nigeria Data Protection Act 2023, for this one purpose, and limited to the data needed. To contribute you must be 18 or older, or have a parent or guardian’s agreement.

7Internet access

The app works offline. When a connection is available it downloads the public community word list from rufixduke.ng. This is a plain download: no identifier, recording or usage information is attached.

As with any internet request, the hosting provider for this website (Vercel) receives your IP address and basic technical details, and may keep them briefly in server logs for security and reliability. I do not use these logs to identify or profile app users.

8Permissions

Camera. Required, to read your hand signs on the device.
Notifications. Optional, and only asked for if you turn on the daily practice reminder. Reminders are scheduled by your phone and involve no server.
Internet. Used only to download the community word list.
Vibration. For haptic feedback when a letter is recognised.

9Third parties

Your information is not sold, rented or shared with advertisers. The app includes no advertising or analytics software.

Hand and body tracking uses Google’s MediaPipe library, which runs entirely on your phone. Spoken words use the text-to-speech engine already on your device, which is governed by that engine’s own settings and policy. Apple and Google may collect their own information when you download the app from their stores, under their own privacy policies.

10Retention and deletion

Data on your phone stays there until you remove it. You can:

Delete any word and its recordings in My words.
Delete all contribution recordings, or withdraw consent, on the Contribute screen.
Remove everything by uninstalling the app.

Deleting in the app does not reach files you have already shared. To have a shared contribution removed, email info@rufixduke.ng. For word contributions, include the contribution ID shown in My words. I will delete the file and leave it out of future versions of the recognition models and word list. Versions that have already been released can’t be recalled from other people’s phones, but they contain only combined recognition data, not your individual recordings.

Shared contributions are kept for as long as they are useful for improving the app, or until you ask for them to be removed.

11Security

App data is kept in private app storage that other apps can’t read, and the word list is downloaded over an encrypted connection. Shared contribution files are stored with access limited to the people working on the app. No system is completely secure, so I can’t promise absolute security.

12Children

Nsila can be used by learners of any age, including in classrooms, and it does not collect personal information from anyone while they use it. The optional contribution features require the person to be 18 or older, or to have a parent or guardian’s agreement. If you believe a child has shared recordings without that agreement, email info@rufixduke.ng and they will be deleted.

13Your rights

Under the Nigeria Data Protection Act 2023, and similar laws elsewhere such as the GDPR, you can ask to access, correct or delete personal data about you, withdraw consent at any time, and object to or restrict its use.

Because the app holds almost everything on your own phone, most of this is in your hands already. For anything you have shared, email info@rufixduke.ng and I will respond within 30 days. You also have the right to complain to the Nigeria Data Protection Commission or to the data protection authority where you live.

14This website

This page is hosted on rufixduke.ng, which uses Vercel Web Analytics and Speed Insights to count page views and measure loading speed. These tools do not use cookies and do not identify individual visitors. If you email me, I keep your message and address for as long as needed to reply and follow up.

15Changes to this policy

If the app changes in a way that affects your privacy, this page will be updated and the effective date above will change. Significant changes will also be noted in the app’s release notes.

16Contact

Questions or requests about privacy: info@rufixduke.ng. For help using the app, see the support page.