SweetSpot

Privacy Policy

Overview

SweetSpot is designed with privacy in mind. The app does not require or collect personal data to work — there are no user accounts, no analytics, and no usage tracking, and it requests only the INTERNET permission (no location, contacts, storage, or device identifiers). Optional features let you share anonymous reliability statistics or send feedback — see details below.

Data Processing

SweetSpot fetches day-ahead electricity prices from public APIs:

  • ENTSO-E Transparency Platform — the primary source for all 43 European bidding zones
  • Spot-Hinta.fi — fallback for Nordic and Baltic zones
  • Energy-Charts — fallback for 15 European zones
  • EnergyZero — fallback for the Netherlands
  • aWATTar — fallback for Austria and Germany

These API requests contain only the bidding zone identifier and date range. No personal information is included.

Local Storage

Price data is cached locally on your device to reduce API calls and enable faster results. Your appliance configuration (names, durations, icons, and optional power ratings), saved vehicles (battery size and charging power), and settings (country, zone, language) are also stored locally on your device, along with your subscription status (cached so the app keeps working offline) and per-appliance tap counts (used only for the most-used and recently-used sorting).

On Wear OS, appliance data and settings are synced between phone and watch using the Wearable Data Layer API. This communication stays on your local devices and does not pass through any external server.

If you share your setup as a QR code or link, your appliance and EV-charging configuration is encoded inside the link or QR code itself — it is never uploaded to a server. Only the person you give the code or link to can import it.

No Analytics

SweetSpot does not include any analytics SDKs, crash reporting, or usage tracking. The app makes no network requests beyond fetching electricity prices from the public APIs listed above (optional stats reporting if enabled, and submitting a report if you use Help & support — see below).

Optional Reliability Statistics

You can opt in to sharing anonymous reliability statistics. When enabled, the app periodically sends individual request records for each data source and bidding zone to our server. This data contains:

  • Timestamp of the API request
  • Bidding zone identifier (e.g. “NL”, “DE-LU”)
  • Data source name (e.g. “ENTSO-E”, “EnergyZero”)
  • Device type (phone or watch)
  • Whether the request succeeded or failed
  • Error category on failure (e.g. “timeout”, “server error”)
  • App version number
  • App language (e.g. “en”, “nl”)
  • Payment status (trial, subscribed, or expired)
  • Request duration in milliseconds

This data does not contain device identifiers, location, price data, or any other personal information. It is used solely to improve data source reliability and default ordering.

This feature is disabled by default. You can enable or disable it at any time in Settings.

Help & Support

If you report a problem or send feedback from Settings › Help & support, your message is sent to our feedback service and filed as an issue in our public GitHub repository. The subject and description you write become publicly visible on GitHub, so please don’t include personal details.

If you choose to be notified by email, the address you provide is stored only by our feedback service — it is never shown in the public issue — and is used solely to email you about your own report. Every notification email includes a one-click unsubscribe link that removes the stored address, and you can also ask us to delete it at any time.

Problem reports also include a short, non-personal diagnostics block: the app and Android version, your device model, the app language, the selected price zone, and the active data source. It contains no name, email address, location, or other personal information.

Open Source

SweetSpot is open source and licensed under GPL v3. You can review the complete source code on GitHub.

Contact

If you have questions about this privacy policy, you can open an issue on GitHub.

Last updated: July 2026