Privacy Policy

StackWatch · Last updated: 20 May 2026

StackWatch is operated by Sico Software Ltd, Suite 2/3, Floor 2, 48 West George Street, Glasgow, G2 1BP, United Kingdom (support@sico.software). This policy explains what data we collect when you install StackWatch, how we use it, and your rights under UK GDPR and the Data Protection Act 2018.

1. What data we collect

When you connect StackWatch to your store, we collect and store:

Store information — your Shopify shop domain, shop name, and the read-only Custom App access token you paste to let us query the Shopify Admin API on your behalf.
App billing data — a list of apps installed on your store, their current and historical subscription charges, and plan names, pulled nightly from the Shopify Billing API using your token.
Price alerts — records of price changes detected across billing cycles, including app name, old price, new price, and the date detected.
Contact email — your merchant account email address, used solely to deliver price-change alert emails.
Usage events — anonymised install and feature-usage events (app installed, alert viewed, switch card opened) used to understand how the product is used.

StackWatch does not collect or store customer personal data (names, addresses, payment details, or order history). Order data is not accessed or stored.

2. How we use your data

To populate your billing ledger and 12-month cost trend chart.
To detect price changes across billing cycles and send you email alerts.
To display price change information in the app dashboard.
To operate, maintain, and improve the StackWatch service.
To respond to support requests.

We do not sell your data, use it for advertising, or share it with third parties for their own purposes.

3. Third-party processors

We share data with the following sub-processors to operate the service:

Processor	Purpose	Data shared
Shopify	Platform host; OAuth provider; webhook delivery	Shop domain, OAuth token, billing subscription data
Hetzner Cloud	VPS hosting for the application and database	All data at rest (encrypted volume)
Resend	Transactional email delivery	Merchant email address, alert content
PostHog	Product analytics (self-hosted instance)	Anonymised install and feature events; shop domain as tenant identifier
Sentry	Error monitoring	Error traces that may include shop domain; no customer PII

4. Data retention

Data type	Retention period
Shopify OAuth access token	Deleted within 48 hours of app uninstall
App billing history (charges, installed apps)	Retained while subscription active; deleted within 48 hours of app uninstall
Price alerts	Retained while subscription active; deleted within 48 hours of app uninstall
Usage events (PostHog)	12 months rolling
Error traces (Sentry)	90 days

When you uninstall StackWatch, Shopify sends a shop/redact webhook within 48 hours. On receipt we permanently delete all data associated with your store. You can request earlier deletion by emailing support@sico.software.

5. Your rights (UK GDPR)

You have the right to:

Access — request a copy of the data we hold about your store.
Erasure — request deletion of all data associated with your store.
Portability — receive your billing history data in a machine-readable format (CSV).
Restriction — request that we stop processing your data while a complaint is investigated.
Object — object to processing based on legitimate interests.

To exercise any of these rights, email support@sico.software. We will respond within 30 days. You also have the right to lodge a complaint with the ICO (UK supervisory authority).

6. Security

Your Shopify OAuth access token is encrypted at rest using AES-256. All data is stored on Hetzner Cloud infrastructure within the EU (Falkenstein, Germany). Access to production systems is restricted to named administrators via SSH with key authentication only.

7. Changes to this policy

We may update this policy as the product changes. Material changes will be communicated via email to your merchant account address. The "Last updated" date at the top of this page reflects the most recent revision.

8. Contact

Sico Software Ltd · Suite 2/3, Floor 2, 48 West George Street, Glasgow, G2 1BP
support@sico.software