Your observations.
Your control.

Privacy at a glance

This policy applies to the Spectra iPhone app, its Experimental Watch companion, and its pages on arcsignal.app, operated by Arc Signal LLC. It does not describe our other apps or the independent services you choose to use.

• No account, advertising, tracking, or third-party analytics SDK in Spectra.
• Signal analysis happens on your iPhone. We do not automatically receive your scans, device discoveries, notes, or magnetic readings.
• Saved sessions are local. Spectra marks session storage for exclusion from device backups; iOS controls backup and restore behavior. You can turn off automatic iPhone saving, delete sessions, or reset the app.
• Exporting a report or contacting support is your choice. Files you export may be stored or backed up by your chosen destination. Review the recipient’s privacy practices.

We do not sell Spectra scan data or share it for advertising. The website includes optional, clearly disclosed affiliate recommendations; following those links involves the external providers described below.

Information processed on your iPhone

Depending on the measurements you select, Spectra processes Bluetooth advertisements and signal strength; supported Bonjour service advertisements on your joined local network; and motion and magnetic-field measurements. These observations help explain possible device categories, related signals, changes, and measurement limitations.

Retained evidence may include advertised names, service types, selected manufacturer or service payloads and product metadata, session-scoped identifiers, timestamps, confidence labels, coverage, and bounded measurement summaries or graphs. A saved session can also contain its name and notes you enter, plus the app build and catalog information used to interpret it. Advertised names and your notes can contain personal information about you or others.

New captures also retain the collecting device’s platform, hardware model, operating-system version, and collector app version and build. This collection context is stored locally and preserved when a Watch capture is imported or a saved session is rechecked. It is separate from the app version used to interpret or export the evidence. Older missing details remain unknown. Spectra does not collect personal device names, serial numbers, or persistent device identifiers for this metadata.

Spectra does not capture camera images, microphone recordings, or conversations. Geographic coordinates are requested only when you enable Tag location for an individual iPhone scan, as described below. Spectra does not pair with discovered devices or open application connections to their endpoints. Local-network browsing can send discovery queries visible to other network participants; it is not invisible network activity.

New Bluetooth captures saved on the collecting iPhone may retain a small, capture-specific namespace reference in the protected private history index. This permits an explicit Bluetooth Proximity check to recognize that capture’s framework identities after reopening. It contains no raw Bluetooth framework UUID, does not automatically correlate independent captures, and does not authenticate hardware. Rechecks share the original acquisition reference. Older, imported and Watch results may instead require explicitly confirming a possible match. Only fresh broadcasts supply live readings.

The recognition catalog is bundled with the app and updated through app releases. Spectra does not automatically send observations to an identification server or an AI service. You can deliberately copy a finding or share an export with a service of your choice, as described below.

Saved-session rechecks reinterpret compatible retained radio evidence locally with newer bundled recognition. They do not start new radio discovery, use Apple Intelligence, or upload evidence. A successful recheck creates an independent saved copy, retaining the original capture time and measurements plus its own evaluation time, engine/catalog revisions, and links to the original and source sessions. Its stable naming base and recheck number are retained even if you later rename the copy; a technical archive can include that naming lineage.

Experimental Watch captures

After setup, the Watch can collect and save locally without your iPhone nearby or an internet connection. Your paired iPhone is needed later for identification and detailed review. Reconnecting may allow queued transfers to resume; capture and delivery are separate steps.

The Experimental Watch companion collects bounded Bluetooth advertisements during a user-started, active-screen sweep. Captures can include advertised names, manufacturer and service bytes, signal strength, timestamps, Watch model and OS/build, and random per-attempt identity tokens. The tokens replace framework Bluetooth identity values; they do not make names or payloads anonymous. There is no Watch location, microphone, camera, local-network, or magnetic collection.

The Watch retains up to five captures within 4 MiB each, with the same limits for the paired iPhone’s inbox. New captures automatically queue for your paired iPhone through Apple’s Watch Connectivity. Open Spectra on iPhone to identify retained signals with its installed catalog and save the result to Sessions. Receipt confirmation means durable phone storage, not completed recognition. Watch sweeps save independently of the automatic iPhone scan-saving setting. When space is needed, only confirmed-received Watch copies or already-processed phone inbox copies are retired. Unsent or unprocessed captures are never automatically discarded. No capture is uploaded to Arc Signal or an identification service.

Watch and inbox data use protected local storage marked for exclusion from backups; Apple controls operating-system backup, restore, and paired-device transfer. Sending is not deletion. Watch copies, received inbox copies, imported sessions, diagnostics, and exported files have separate lifetimes. After individual Session deletion, a bounded local record of imported capture IDs remains to prevent delayed transfers from recreating deleted sessions; it contains no broadcast evidence. Erase All Sessions or Reset Spectra clears this record and the received inbox, and invalidates previously queued copies. Erasing captures directly on Watch cancels queued transfers where possible; already delivered or in-flight copies may remain on iPhone.

Separate timing diagnostics retain the latest 20 reports per device. They include model, OS/build, dates, receipt counts, lifecycle events, and completion timing, but exclude nearby-device names, identity values and advertisement payloads. Older diagnostic reports age out. Share Watch diagnostics is user-initiated; nothing is sent to support automatically. These reports are not anonymous because dates and hardware details can reveal context.

Erase Watch captures and Erase Inbox Copies each remove capture copies in their own store, not imported Sessions or copies on the other device. Erase All Sessions also clears received Watch inbox captures but does not request a Watch reset. Reset Spectra additionally clears received timing diagnostics and preferences, then requests erasure of captures, diagnostics, and preferences in the known paired Watch app. Watch reset pending is not confirmation: an offline Watch may still hold data. Watch reset confirmed appears only after the Watch reports completion. Open both apps and review the Apple Watch section in iPhone Spectra Settings. If the Watch app has not introduced itself or needs updating, open or update both apps, then explicitly choose Reset Watch and confirm. A newly paired or reinstalled Watch is not automatically erased by an older request. Exported files and system permissions remain. Read the Experimental Watch guide before erasing data you need. An unfinished capture can be lost if the app is terminated before saving.

A small protected reset-control record remains on each device to finish pending requests and reject stale commands or transfers. It contains random coordination identifiers and request status, not captured signals. Repeated delivery of a completed request does not erase a new sweep. Confirmation records completion of that request; it does not prevent later collection.

Only the access you choose

Bluetooth permission enables available advertisements. Local Network permission enables supported service discovery on a joined network. Motion access and available magnetic hardware support magnetic exploration during Area Sweep. You may skip setup or select fewer measurements; Spectra checks access again before scanning and explains unavailable sources.

The optional Show Wi-Fi name action requests Location permission, including Precise Location While Using the App where iOS requires it. That action does not request coordinates or save the Wi-Fi name in history; it clears the displayed name when the app backgrounds. Granting this permission does not turn on scan location tags.

Tag location is off by default for every new iPhone scan. If you enable it, Spectra requests one fix near collection start, retaining coordinates, the fix time, estimated accuracy, and collector platform. It does not track a route, infer detected devices’ locations, or add the phone’s current position to an older or Watch capture. Acquisition is bounded to 12 seconds; stale, invalid, or excessively imprecise fixes are discarded. Denied access or an unavailable fix never prevents scanning. Approximate locations can be retained when they meet the same validity checks. No tag is requested on Watch.

A saved tag is protected local session metadata. Rechecks preserve the original tag; they do not acquire a new location. Remove location removes it from that saved copy, not independent rechecks or files already shared. Protected recovery copies, if present, are cleared by Erase All Sessions or Reset Spectra. The app shows coordinates without an address lookup. Map previews require a separate, remembered opt-in.

Enable map previews authorizes automatic requests for maps of saved areas through Apple Maps when viewing tagged results. No preview request runs before enabling. Not now is remembered without repeated prompts. Change Automatic map previews in the Session maps section of Spectra Settings at any time. Disabling cancels pending work and clears the temporary image; Reset Spectra also clears the preference. Deleting sessions does not change the preference. Open in Maps separately passes the saved coordinates to Maps. Neither action requests your current position through Spectra. These optional actions use Apple’s map data practices, which describe map-area and operational information handling. A preview represents the collecting iPhone’s saved position and estimated accuracy, not detected devices or a verified venue.

Spectra does not save preview images in sessions or exports. It clears its temporary preview and cancels pending work when you leave the results, switch away from the app, or change the tag; returning can reload the preview while Automatic map previews remains enabled. An unavailable preview does not prevent reviewing saved coordinates or findings. Clearing a preview, removing a tag, or resetting Spectra does not erase Apple’s service records or system-managed map caches.

All JSON formats omit location by default. Enabling Include scan location for a single-session export adds coordinates, accuracy, and the fix timestamp, even with Reduced identifying information. A collection uses Include scan locations. Location tags are excluded from on-device AI evidence, the text prepared by Use Another App, and support diagnostics. Advertised names or notes may still reveal a place. Scanning works without Location access.

Review or revoke access in iOS Settings. Resetting Spectra does not reset Apple’s permission decisions. Measurement is foreground-only, not background surveillance.

Keep what matters. Erase what does not.

With automatic iPhone saving off, Save Session on completed results keeps just that check without changing your preference. Confirm its saved status before closing; an unsaved result can be lost when the app closes. Search sessions searches saved names, notes, check types, and source metadata locally, not every device name or payload inside your captures. Neither library search nor Search Guide uploads scan evidence.

Completed iPhone checks are saved by default in the app’s local storage. Turn off Save completed sessions in Spectra Settings to stop automatic saving of future iPhone checks; existing sessions remain until deleted. Deliberate file imports and rechecks, and Watch processing, save independently of that preference. The primary history file keeps up to 500 sessions within a 256 MiB budget. Originals, rechecks, and imported copies count separately toward these independent limits. Saved sessions are not automatically removed to make room. View usage in Sessions, or choose Session storage under Privacy & storage in Spectra Settings; primary history bytes are not export size or total app disk allocation. Temporary replacement files, protected recovery copies, and the separate Watch inbox can require additional space. A lightweight index lists sessions. Retained evidence is read locally when you open or recheck a session, or when an update refreshes compatibility metadata; browsing history does not run a new scan. Long-running measurement traces and event histories are also bounded.

Import Sessions reads a supported full Technical archive JSON or a Spectra ZIP collection selected in Files or handed to Spectra by another app. Other ZIP files are not accepted. You review metadata, integrity, and any already-saved copies before confirming a local save. A collection adds every new accepted session together or none. Already-saved copies stay unchanged and use no additional slots; conflicting same-ID contents, invalid members, or insufficient capacity block the collection rather than overwrite history or silently import a subset. A chosen cloud/provider file may need a connection to become available; validation and history saving run on device. Import does not alter the source file, automatically start measurements, analysis, a recheck or a map, or remove another session. Imported records retain the file’s acquisition and interpretation context with a separate Imported qualifier; those recorded facts, names, notes and any included coordinates remain unverified. A checksum checks archived bytes, not origin or authenticity. Supported older archives without a checksum remain explicitly unchecked. Failed integrity checks and unsupported archives are blocked. Import does not restore private Bluetooth follow-up references.

Saved reports and notes use iOS file protection. Protected recovery copies remain until deliberate erasure; Erase All Sessions and Reset Spectra include them. Creating another recovery copy does not automatically remove an earlier one; device storage remains finite. New on-device AI explanations are temporary: they are not saved in sessions or included in exports. Older sessions may still contain explanations saved by an earlier app version; deleting those sessions removes that local history too. Spectra marks the session directory, including recovery copies, for exclusion from device backups. This is not a guarantee that sessions can never appear in a backup or on a restored device; iOS controls backup and restore behavior. Files you export may be stored or backed up by your chosen destination.

Recheck copies use additional local storage and count toward the same session limit. A recheck never removes another session to make room. Deleting the original does not delete its independent rechecks or erase their naming lineage. Delete the copies you no longer need, or use Erase All Sessions or Reset Spectra for the app-wide actions described below. Turning off automatic saving of future iPhone checks does not prevent an explicitly requested recheck from saving a new copy.

Private Bluetooth follow-up references follow the same protected history transaction and backup-exclusion policy. They are bounded and optional. A failed save preserves previously committed sessions and their retained references; Spectra does not silently remove valid references to make the new save fit. Corrupt or unavailable references are not used. Removing the last non-imported original or recheck copy retires its reference; imported copies cannot keep it. Individual Undo may briefly restore it with the session. Erase All Sessions and Reset Spectra clear the retained references. Protected recovery copies follow the erasure details below.

A privacy cover obscures sensitive app content when the app is no longer active. These protections do not make a report tamper-evident or guarantee protection on an unlocked or compromised device.

If a history file is damaged, Spectra pauses changes and may preserve a protected local recovery copy. Recovery copies remain until deliberate erasure; another recovery attempt does not remove an earlier copy. Preserving or saving can still fail when device space or protected access is unavailable. A temporary storage-access failure is retried and is not treated as permission to overwrite your history.

In Sessions, delete one report or select several. Open Storage → Session Storage for Erase All Sessions; it includes all saved history, closed groups, recovery copies, and received Watch inbox captures, regardless of search or filters. It does not erase Watch copies or request a Watch reset. Reset Spectra in Spectra Settings also clears preferences and returns to Welcome, then asks iOS to restore the Classic app icon. An unconfirmed cosmetic icon change does not undo data erasure. Both all-data actions remove app-owned temporary JSON handoff files; failures are reported rather than described as successful erasure. Individual deletion removes that report from primary history, not older recovery copies—use Erase All Sessions or Reset Spectra for those.

After individual deletion in the main Sessions list, Undo can restore the most recently deleted report for 10 seconds, or 30 seconds when VoiceOver is running at deletion. The saved report is removed first; one recovery copy remains temporarily in app memory, not in a Recently Deleted folder. Another deletion replaces it. The opportunity ends when it expires, you leave Sessions, Spectra becomes inactive, or you confirm bulk deletion or reset. Largest Sessions in Session Storage lists each saved copy by estimated size. An unavailable size is not zero; estimates may differ from reclaimed bytes. Deleting there requires confirmation instead of offering Undo and removes only the chosen session, not other saved versions. Delete Selected, Erase All Sessions, and Reset Spectra clear pending Undo and cannot be undone.

Erasure cannot recall copies saved outside Spectra, shared with another app or person, or retained by a service you selected. It also cannot remove mail you sent to support; contact us separately about that information.

Optional Apple Intelligence analysis

Analyze on Device is optional and user-initiated. You choose one finding. Spectra passes only its high-level summary to Apple’s on-device language model, not the whole scan, raw measurement histories, notes, or other findings. Magnetic input contains incident counts and up to three strongest retained peak summaries. This feature does not send scan data to Arc Signal, an external AI provider, or Private Cloud Compute. Generated explanations exist only in the analysis view’s memory. They are cleared when you close that view or choose another finding, are not saved with sessions, and are excluded from every JSON export. Using analysis does not enable history saving or create a saved scan.

On-device analysis requires Apple Intelligence-capable hardware. Model availability also depends on Apple Intelligence settings, model readiness, language, and region. Scanning, saved results, and JSON export do not depend on Apple Intelligence. Earlier app versions may have retained generated analysis with a saved session. Those legacy records are no longer displayed or exported and are removed when the corresponding session is deleted, subject to the recovery-copy and external-copy details above.

Spectra has no in-app purchase or purchase-verification step. We do not collect payment-card details or attach purchase information to exported scan evidence.

You decide when data leaves the app

Private Bluetooth follow-up references are not part of scan reports and are never included in JSON exports, Spectra ZIP collections, AI evidence, support-information copies, Watch transfers, or diagnostic reports.

Export JSON prepares a report locally. Analysis JSON contains meaningful retained observations, device claims, scan coverage, user notes, and recorded collection context. The technical archive also includes retained raw data and graphs. All formats exclude generated AI explanations, including any legacy saved analysis. Reduced identifying information may retain the collector platform, but omits collector hardware and OS version, names, notes, original identifiers, manufacturers, model labels, raw payloads, and absolute timestamps. App and recognition versions remain, including the original capture build for rechecks. It is not anonymous: patterns and relative timing can still reveal context. Results filters do not restrict any export.

Export All Sessions in Session Storage prepares one ZIP of Technical archives from the saved-history snapshot when preparation starts. This is not a full app backup: it excludes preferences, generated AI explanations, private Bluetooth references, unsaved results, and Watch captures not yet added to Sessions. Location tags are excluded by default; Include scan locations deliberately includes saved coordinates, estimated accuracy, and fix timestamps in the collection. Exporting does not remove local history or free space.

Export Selected prepares the same kind of ZIP after privacy review, with only the exact saved sessions chosen in Sessions. Search and filters stay fixed while selecting; an original does not include its rechecks automatically, and original-capture context cannot be selected. Location tags are excluded by default, and the same collection exclusions apply. Names, notes, and raw retained payloads can contain identifying information. A Spectra ZIP can be imported directly after review; exporting leaves saved history unchanged.

Export JSON, Export All Sessions, and Export Selected open Apple’s share sheet, where you can choose Save to Files or another destination. A destination such as iCloud Drive, email, another app, or an external AI provider may transfer or retain your file under its own terms and privacy policy. Spectra does not send it to us automatically. Review the file, recipient, and destination before sharing; do not share information you are not authorized to disclose.

Use Another App offers one optional review before you choose Share or Copy. Selecting one finding prepares an analysis prompt followed by bounded finding evidence locally. Review the exact preview and privacy notice before continuing. Optional technical evidence can include identifying names or payloads; the default text is not anonymous either. Both actions exclude session notes, location tags, other findings, and generated AI text, and neither requires Apple Intelligence.

Share opens Apple’s share sheet with the prepared text. Some destinations may send it immediately. The app or destination you choose handles it under that recipient’s policies; Spectra cannot verify its processing or retention. Available destinations depend on installed apps and the text they accept. Only tapping Copy writes Spectra’s on-device-only clipboard item with a ten-minute expiration. This limit applies to that clipboard item, not shared text or copies made by recipients. Pasting shares the text with the receiving app. Selecting a finding or opening its preview does not share it automatically. Clipboard expiration, session deletion, or Reset Spectra cannot recall information already shared, pasted, exported, or otherwise copied elsewhere.

Support and diagnostics

Read public support articles on Arc Signal’s website. For email support, contact support@arcsignal.dev. If you contact us, we receive your email address, message, and any details or attachments you choose to submit. We use them to respond, troubleshoot, and improve reliability. Start with a description of the problem, not private scan data.

Choose Settings → Support information → Copy support information to copy the app version and build, iOS version, hardware model, detection-engine revision, and catalog revision. The copy excludes scan history, network names, geographic location, and persistent personal identifiers. Copying is user-initiated, local to the device’s clipboard, and expires after ten minutes. Nothing is emailed automatically.

We retain support correspondence only as long as needed to address the request, maintain relevant support records, and meet applicable legal obligations. Google Workspace handles support email; Zoho Desk handles support tickets and replies. Changing our support provider does not automatically migrate or erase earlier correspondence; those records remain subject to the retention purposes above. We do not embed a support widget or SDK in Spectra or the Arc Signal website, or use support messages for advertising. We may disclose information where legally required or necessary to protect rights and safety.

Apple independently operates the App Store and iOS diagnostic services. Depending on your Apple settings, Apple may collect or share crash and diagnostic information with developers. Any such information available to us is used for reliability and support. Spectra does not add its own automatic analytics or crash-upload SDK.

When you visit our website

The Arc Signal product website at arcsignal.app uses no analytics scripts, tracking pixels, contact forms, or embedded third-party services. Fonts and images, including the NordVPN logo, are self-hosted. Visiting the privacy policy, Guide, or support articles is a normal website request, not a scan-data upload. We do not contact NordVPN, Google Workspace, Zoho Desk, or Stripe or load their scripts when you browse our pages. Choosing an email support link opens your mail app; nothing is attached or sent automatically.

Optional development contributions use a separate Stripe-hosted checkout. Following Support our work opens Stripe; no scan data or personal identifiers are appended to the link, and we suppress the referring page. Stripe processes the contact and payment information you enter and connection information such as your IP address, and may use cookies or similar technologies. Arc Signal may receive contact details and transaction records, such as the amount, date, payment status, and limited payment-method details, to administer contributions, handle payment questions, and meet accounting and legal obligations. Our website does not receive your full card number. We retain contribution records as needed for those purposes, separately from on-device scan history. Review Stripe’s privacy policy. Contributing is optional and does not purchase the app, unlock features, or provide priority support.

Arc Signal participates in the NordVPN affiliate program. We may earn a commission if you purchase through a NordVPN recommendation link, as disclosed beside each link. These are ordinary links, not embedded services. Following one takes you through NordVPN’s referral service to its website. The link contains our affiliate and offer identifiers, not an identifier generated for you. No scan data is attached to these links.

After you follow the link, NordVPN and its referral providers receive connection information, such as your IP address and browser details. They may use cookies or similar technologies to attribute a visit or purchase to Arc Signal and report referral activity for commissions. Our links suppress the referring page, but this does not hide your IP address or prevent the destination’s own tracking. Review Nord’s privacy policy and the destination’s cookie choices before using its services. You can use Spectra without visiting NordVPN or buying a VPN.

Our website is hosted through GitHub Pages. Its provider may process routine request information, such as IP address, requested page, browser details, and request time, to deliver and secure the site. Provider retention and processing follow the GitHub General Privacy Statement. Apple, your email provider, and export destinations have their own privacy practices. Provider processing may take place in countries other than yours.

Questions and privacy choices

You control app permissions, local saving, erasure, exports, and support sharing. We cannot remotely access, retrieve, or erase scan history that stays exclusively on your iPhone.

Depending on applicable law, you may have rights to access, correct, delete, or restrict use of personal information you have provided to us, or to raise a concern with a privacy regulator. Contact support@arcsignal.dev with “Privacy request” in the subject. We may ask for limited information to verify and handle your request; do not send scan history just to verify your identity.

Children

Spectra is not directed to children under 13. We do not knowingly request personal information from children. If you believe a child has sent personal information to us, contact support so we can address it.

Changes to this policy

We may update this policy as Spectra, our service providers, or requirements change. The effective date above identifies the current policy. Material changes will be explained here and, where required, through an appropriate notice or consent flow. The policy is available from Welcome and Settings → About Spectra → Privacy policy in Spectra.