dusal

dusal Privacy Policy

Effective date: 7 November 2026

dusal ("the app", "we", "us") is an app for learning the traditional Mongolian script. It is made and run by an individual developer, Ankhbayasgalan Davaadorj. This policy explains what we collect, why we collect it and what you can do about it. The short version: we keep your phone number and your learning progress, and nothing else. We show no ads, we don't track you, and we never sell your data.

1. What we collect

Data Why Where it comes from
Phone number To create your account and let you sign in without a password You enter it
Learning progress: lessons completed, XP, level, streak and freezes, crowns, badges, gems, quests, league standing, daily goal setting To save your progress and run streaks, quests and leagues Created as you use the app
An internal account ID To link your progress to your phone number Created by us
Display name (optional, up to 40 characters) To show you in your weekly league You set it in Тохиргоо (Settings), and you can change or remove it at any time

Apart from the optional display name, we do not collect your name, email, contacts, location, photos, microphone recordings or advertising identifiers. We do not read your SMS messages. Letter-tracing exercises are checked on your device.

Our hosting provider may keep short-lived technical logs, such as IP addresses and request times, to keep the service secure and working. We don't use them to profile you.

2. How signing in works

dusal has no passwords. You enter your phone number, and then you send a short code by SMS from your own phone to 150073. The SMS verification service 2fa.mn receives that message and tells us that the number belongs to you. Your mobile operator (Unitel, Mobicom, Skytel, G-Mobile or ONDO) charges 150₮ for that one SMS. We don't receive this payment.

3. Who processes your data

We use two service providers. They process data only to provide their service to us:

  • 2fa.mn: SMS verification. It receives your phone number and the verification SMS.
  • Railway: hosting and database. Your account and progress are stored on servers in the United States.

We do not sell, rent or share your data with anyone for advertising or marketing. We may disclose data if the law requires it.

4. What other users see

Other learners in your weekly league group see your display name, your rank and your weekly XP. If you haven't set a display name, they see «Суралцагч» ("Learner"). Don't use your full real name if you'd rather stay anonymous. Other learners never see your phone number.

5. How long we keep data

We keep your data while your account exists. When you delete your account, we delete your phone number and progress within 30 days. Backups are overwritten on their normal cycle.

6. Deleting your account

You can delete your account at any time:

  • In the app: Профайл → Тохиргоо → Бүртгэл устгах (Profile → Settings → Delete account)
  • On the web: https://dusal.app/delete-account
  • By email: write to info@dusal.app. Before deleting, we will confirm that the number is yours, for example by asking you to sign in.

7. Your choices and rights

You can ask us for a copy of your data, ask us to correct it or ask us to delete it. Email info@dusal.app and we will reply within 30 days. You may also have rights under the laws of the country where you live, including Mongolia's Law on Personal Data Protection.

8. Children

dusal is meant for people aged 13 and over. Younger children may use it only with a parent's or guardian's consent. If you think a child under 13 created an account without consent, contact us and we will delete it.

9. Security

Data is encrypted in transit (HTTPS). Access to the database is limited to the developer. No system is perfectly secure, but we keep the data we hold to a minimum.

10. International transfer

Our servers are in the United States, so your data is transferred there and stored there. By using dusal, you understand that your data will be processed in the US.

11. Changes

If we change this policy, we will update the effective date above. If a change matters, we will also tell you in the app before it takes effect.

12. Contact

Монгол хувилбар: Нууцлалын бодлого