Privacy notice
In short: your microphone's sound never leaves your device. We keep the little we need to run your account (your email address, your plan and some security records), we don't sell or share it for advertising, and we don't use tracking or analytics.
Last updated 15 October 2026.
Who we are
TrueStrobe is made by Selfe Guitars, the trading name of Matt Selfe, a sole trader in the United Kingdom. We are the "controller" of the personal information described here. This notice covers the TrueStrobe tuner at app.selfeguitars.co.uk.
Questions, or want to use your rights? Email tuner@selfeguitars.co.uk.
Your microphone and recordings
The tuner listens to your instrument through your browser. All the sound analysis happens on your own device:
audio is never sent to us or anyone else, and nothing is recorded. The optional diagnostics view
(/tuner?diag=1) can save 10 seconds of input to a file on your device; it only leaves your device if you
choose to share it.
What we collect, and why
| Information | Why we need it | Legal basis |
|---|---|---|
| Your email address | Your account, and sending your sign-in codes and service emails (trial reminders, receipts from Stripe). | Contract |
| A normalised form of your email (for example, Gmail dots removed) | Making sure each person gets one free trial. | Legitimate interests (preventing abuse) |
| Account details: when you joined, your trial dates, your plan and when it renews or ends | Knowing what you have access to. | Contract |
| Stripe reference numbers for your customer record and subscription, and its status | Linking your payments to your account. We never see or store your card details. | Contract |
| Signed-in devices: a random code (we store only a scrambled version), when it was last used and your browser type | Keeping you signed in. | Contract |
| Tuning sessions: when the tuner started and was last running | Your plan's limit on devices in use at once. | Contract |
| A security log: sign-ins, sign-in codes requested, repeated trials and unusual activity, with your IP address | Keeping accounts secure and stopping misuse of trials and sign-ins. | Legitimate interests (security, fraud prevention) |
We don't send marketing emails, we don't show adverts, and we don't use analytics, tracking pixels or social media trackers.
Who else handles your information
We use a few trusted providers, only for the purposes above:
- Cloudflare hosts the tuner and its database (stored in Western Europe), protects the site, and runs the "are you human?" check on the sign-in page (Cloudflare Turnstile).
- Postmark sends our emails (sign-in codes and trial reminders).
- Stripe takes payments. When you buy a plan, Stripe handles your payment details and acts as the seller of record, collecting the right tax; its own privacy policy applies to that.
Some of these providers are based in, or may process data in, the United States. Where that happens, the transfer is protected by the UK's approved safeguards (such as the UK–US Data Bridge or standard contractual clauses).
We never sell your information, and only share it with others if the law requires us to.
Cookies and storage on your device
We use one cookie: it keeps you signed in on that device, and lasts 30 days from when you last used the tuner. It's strictly necessary for the service, so it doesn't need your consent. The tuner also remembers your settings (such as theme and tuning presets) in your browser's local storage; they stay on your device. There are no advertising or analytics cookies.
How long we keep it
- Sign-in codes: deleted after 24 hours (they stop working after 10 minutes).
- IP addresses in the security log and trial records: removed after 90 days.
- The security log itself: deleted after 12 months.
- Signed-out or expired devices, and tuning sessions: deleted 90 days after they end. We keep the date of your most recent sign-in, so we know whether your account is still in use.
- Your account: until you ask us to delete it, or 2 years after you last used it if you have no active plan.
- A record that a free trial was used (your normalised email only): kept, so the trial can't be claimed twice.
- Payment and tax records: kept by Stripe for as long as the law requires (6 years in the UK).
Your rights
You can ask for a copy of your information, ask us to correct it, delete it, restrict or object to how we use it, or ask for it in a portable format. Email tuner@selfeguitars.co.uk; we'll reply within one month. If you delete your account while you have a paid plan, you can cancel the subscription in "Manage subscription" first.
If you're unhappy with how we've handled your information, please tell us. You can also complain to the Information Commissioner's Office: ico.org.uk, telephone 0303 123 1113.
Children
TrueStrobe isn't intended for children under 13, and we don't knowingly collect their information.
Keeping it safe
The site is only available over an encrypted connection. Sign-in codes and device codes are stored scrambled, not in readable form, and access to the database is limited to us.
Changes
If we change this notice we'll update the date at the top, and tell you by email if the change is significant.