Filaments — Tweet Geek

Document: Terms of Service for Filaments Last updated: 2026-04-24

1. General provisions

These terms of service govern the use of the mobile application Filaments (the “App”), owned by Sebastian Dawidziak, doing business as Tweet Geek Sebastian Dawidziak (the “Provider”).

Using the App means full acceptance of these terms. If you do not accept any of these provisions, do not use the App.

2. Definitions

User — a natural person using the App.
Account — set of data identifying the User in the App.
Store — the App Store (Apple) or Google Play (Google).

3. Technical requirements

Use of the App requires a mobile device running iOS 15+ or Android 9+ and an active internet connection.

4. Rules of use

Using the App in a manner inconsistent with law or good manners is prohibited.
Actions intended to disrupt the operation of the App are prohibited.
The User is responsible for content they enter into the App.

5. Payments and subscriptions

Some App features may require a paid subscription handled by the Store. Payment, renewal and refund rules are governed by the terms of the relevant Store.

6. Complaints

Complaints can be sent by email to sebastian@tweetgeek.pl. Complaints are processed within 14 business days.

7. Final provisions

The Provider reserves the right to amend these terms. The current version is always available at this address. Matters not regulated herein are subject to Polish law.

Document: Privacy Policy for Filaments Last updated: 2026-04-24

1. Data controller

The controller of personal data processed in connection with the use of the Filaments app is:

Sebastian Dawidziak / TweetGeek
E-mail: sebastian@tweetgeek.pl

For any questions regarding the protection of your personal data, please contact us at the e-mail address above.

2. What is the Filaments app?

Filaments is a mobile app for managing 3D printing filament spools. It lets you track inventory levels, usage history, scan barcodes and QR codes, and read/write NFC tags attached to your spools. All spool data is stored exclusively on your device.

3. What data we collect and why

3.1 Data stored locally on your device

The app stores the following data on your device (SQLite database):

filament spool details (name, colour, manufacturer, weight, status)
usage history and print jobs
app settings and user preferences

This data is never sent to any external servers — it stays exclusively on your device. Uninstalling the app permanently deletes it.

3.2 Camera

The app requests camera access solely to scan QR codes and barcodes on filament spools. The camera feed is never recorded or transmitted outside your device — it is processed locally only during an active scan.

3.3 NFC

NFC access is used exclusively to read and write NFC tags attached to filament spools. Communication happens directly between the device and the tag — no data is sent over the network.

3.4 Purchases and subscriptions (RevenueCat)

In-app purchases (Premium subscription) are handled by RevenueCat. During the purchase process, data required to complete the transaction is processed (device identifier, purchase information from Google Play / App Store). RevenueCat does not receive your payment details — these are handled directly by Google Play or the App Store.

RevenueCat Privacy Policy: revenuecat.com/privacy

3.5 Usage analytics (PostHog)

We use PostHog to understand how the app is used and to improve it. Anonymous analytics data is collected, such as:

which screens are visited and how often
which features are used
device information (model, operating system version)

This data does not contain information that could directly identify a person. PostHog’s automatic initialisation is disabled — data is only sent after the app has launched.

PostHog Privacy Policy: posthog.com/privacy

3.6 Crash reporting (Sentry)

We use Sentry to detect and fix app errors. When a crash or unhandled exception occurs, an automatic report is sent to Sentry containing:

stack trace and error message
app version and operating system version
device model

Reports do not contain personal data or the contents of your spool database.

Sentry Privacy Policy: sentry.io/privacy

3.7 Advertising (Google AdMob)

Users on the free version of the app may see ads served by Google AdMob. Google may use the device’s advertising identifier (IDFA / GAID) to show personalised ads, provided you have given your consent (depending on your device settings and CMP consents).

Premium users do not see ads — AdMob is not initialised for them.

Google Privacy Policy: policies.google.com/privacy

Purpose	Legal basis
Local storage of spool data	Art. 6(1)(b) GDPR — performance of a contract (provision of the service)
Purchase handling (RevenueCat)	Art. 6(1)(b) GDPR — performance of a contract
Usage analytics (PostHog)	Art. 6(1)(f) GDPR — legitimate interests of the controller (improving the app)
Crash reporting (Sentry)	Art. 6(1)(f) GDPR — legitimate interests (app stability and security)
Personalised advertising (AdMob)	Art. 6(1)(a) GDPR — user consent

5. International data transfers

Some data (PostHog, Sentry, RevenueCat, Google AdMob) may be processed on servers located outside the European Economic Area, in particular in the United States. Transfers are carried out with appropriate safeguards — these providers comply with Standard Contractual Clauses (SCCs) or have other approved transfer mechanisms in place that are compliant with GDPR.

6. Retention periods

Local data (spools, history) — stored on the device until the app is uninstalled or manually deleted by the user.
Analytics data (PostHog) — in accordance with PostHog’s retention policy (1 year by default).
Crash reports (Sentry) — in accordance with Sentry’s retention policy (90 days by default).
Purchase data (RevenueCat) — for the period necessary to manage subscriptions and billing.

7. Your rights

As a user, you have the following rights:

Right of access — you may request information about the data we process.
Right to rectification — you may request correction of inaccurate data.
Right to erasure — you may request deletion of your data (the “right to be forgotten”).
Right to restriction of processing — you may request restricted processing in certain cases.
Right to data portability — you may receive your data in a structured, machine-readable format.
Right to object — you may object to processing based on legitimate interests.
Right to withdraw consent — at any time, without affecting the lawfulness of processing before withdrawal (applies to advertising data).

To exercise any of these rights, please contact us at: sebastian@tweetgeek.pl.

You also have the right to lodge a complaint with a supervisory authority. In Poland, this is the President of the Personal Data Protection Office (UODO) (uodo.gov.pl). Users in other EU/EEA countries may contact their local data protection authority.

8. Data security

We apply appropriate technical and organisational measures to protect data against unauthorised access, loss or destruction. Sensitive configuration data (e.g. tokens) is stored using the secure system keystore (Android Keystore / iOS Secure Enclave).

9. Children

The app is not intended for children under the age of 13, and we do not knowingly collect personal data from such persons. If you believe a child under 13 has provided us with their data, please contact us — we will delete it promptly.

10. Changes to this privacy policy

We reserve the right to update this privacy policy. We will notify you of material changes by updating the date in the document header and, where appropriate, through an in-app notification. We recommend checking this page periodically.

11. Contact

If you have any questions or concerns about this privacy policy, please contact us: