Desenhama ("Desenhama," "we," "us," or "our") is operated by Lucas Guilherme Lima da Silva. This Privacy Policy explains how Desenhama collects, uses, stores, and shares information when you use the Desenhama Android application and its related services.
If you have questions or want to exercise your privacy rights, contact us at lguilherme8@gmail.com.
Information we collect
Desenhama does not require you to provide a name, email address, phone number, or social-media account. The service uses anonymous technical identifiers to connect the app to its backend and to pair two installations.
We process the following information:
- Drawings: the PNG preview you send, the drawing's canvas dimensions, colors, stroke widths, stroke coordinates, and creation time.
- Pairing information: a randomly generated device identifier, the identifier of the paired device, and temporary pairing codes. Pairing codes expire automatically.
- Authentication information: a randomly generated device credential. The credential is kept in protected storage on your device, and the backend stores a cryptographic hash of it.
- Notification information: a Firebase Cloud Messaging registration token used to notify your device when your partner sends a drawing.
- Information stored locally: the latest sent and received drawings, widget display preferences, drawing-color preferences, notification preferences, and the protected device credential are stored on your device.
- Basic service communications: our hosting infrastructure may process technical request information that is ordinarily necessary to deliver and secure an internet service, such as timestamps, network addresses, and request diagnostics.
How we use information
We use this information only to:
- register and authenticate an app installation;
- pair one Desenhama installation with another;
- send a drawing to the paired device and display it in the app or home-screen widget;
- send drawing-arrival notifications;
- preserve the editable representation and preview of a drawing;
- operate, secure, diagnose, and maintain the service; and
- respond to privacy, support, or deletion requests.
Desenhama does not use your drawings or technical information for advertising, profiling, or sale. The app does not include advertising or analytics services.
How information is shared
The content of a drawing you send is made available to the single device paired with yours. We do not make drawings public.
We use service providers to operate Desenhama. These providers process data on our behalf for the purposes described above:
- Google Firebase Cloud Messaging delivers drawing-arrival notifications and processes notification registration tokens.
- MongoDB stores anonymous device records, pairing relationships, notification tokens, and drawing metadata.
- Cloudflare R2 stores drawing preview images in private object storage.
- Fly.io hosts the Desenhama backend service and routes requests to it.
These providers may process technical information according to their own privacy terms and the configuration of our services. We may also disclose information when required by law, to protect the security and rights of users or the service, or as part of a business transfer where permitted by law.
We do not sell personal information.
Data security
Desenhama uses reasonable technical and organizational safeguards. Network communication with the production service is encrypted in transit using HTTPS. Drawing previews are stored in private object storage and are delivered through an authenticated API. Device credentials are stored in encrypted Android storage, and the backend stores only a cryptographic hash of each credential.
No method of transmission or storage is completely secure, so we cannot guarantee absolute security.
Data retention
Temporary pairing codes expire automatically. At present, device records, pairing relationships, notification tokens, drawing metadata, and drawing previews are retained while the service is operating unless deletion is requested. We may retain limited information for longer when reasonably necessary to comply with law, resolve disputes, prevent abuse, or enforce agreements.
Drawings and preferences stored locally remain on the device until they are replaced, the app's data is cleared, or the app is uninstalled.
Deletion and your choices
You may disable drawing notifications in Desenhama's settings or through Android system settings.
To request deletion of the server-side information associated with your Desenhama installation, email lguilherme8@gmail.com with the subject "Desenhama data deletion request." We may need to ask for information available from the app to identify the anonymous installation. Once verified, we will delete the associated device record, pairing relationship, notification token, drawing metadata, and drawing previews, except information we must retain for legal or security reasons.
You can delete locally stored Desenhama data by clearing the app's storage or uninstalling the app. Uninstalling the app alone does not notify us to delete server-side data.
Depending on where you live, you may have rights to access, correct, delete, restrict, or obtain a copy of information associated with you, or to object to certain processing. Contact us to make such a request.
Children's privacy
Desenhama is not directed to children under the minimum age required to consent to data processing in their country. We do not knowingly collect personal information from children. If you believe a child has provided information through Desenhama, contact us so we can review and delete it where appropriate.
International data processing
Our service providers may process information in countries other than the country where you live. Where required, we take appropriate steps to protect information transferred internationally.
Changes to this policy
We may update this Privacy Policy when Desenhama or its data practices change. We will publish the revised policy at the same public URL and update the effective date. If a change materially affects how information is handled, we will provide additional notice when required.
Contact
Lucas Guilherme Lima da Silva
Brasília, Distrito Federal, Brasil
lguilherme8@gmail.com