Arc Signal LLC
Privacy-minded tools to help you understand your surroundings, explore the evidence, and decide what deserves a closer look.
Meet Spectra
From a quick check to a closer look, Spectra brings electronic observations and their meaning into one place.
The signals are there.
Make sense of them.
Explore nearby Bluetooth signals and local-network services. Use repeatable, close-range magnetic changes to guide a closer physical look—not to confirm a hidden device.
Explore SpectraiPhone · iOS 27 or later
Spectra · For iPhone
On-device processing
No account required
No in-app ads
Everyday awareness
Hotels, Airbnb stays, student housing, rideshares, gyms, changing rooms, and travel hubs can leave you wondering what is nearby. Spectra helps you review available signals—not certify a space or identify who is carrying a device.
The Arc Signal approach
Arc Signal builds Spectra to make security awareness more approachable. Useful observations, understandable results, and honest limits guide every decision.
Start a check, review what was observed, and follow the evidence. Recheck eligible saved sessions with newer recognition while keeping the original unchanged.
Spectra processes scans and Apple Intelligence analysis on your device. No account to create, no ads, and no analytics in the app.
We regularly improve Spectra’s device catalog and detection engine to help you understand more. These improvements are included in App Store updates at no additional charge.
Privacy, in practice
Your observations stay with you.
Spectra can explain one selected finding locally with Apple Intelligence. Explanations are temporary, not saved with scans or included in exports. You decide what to inspect, keep, and share.
Explore the privacy policy for details on local storage, exports, and the system services you choose to use.
This website uses no analytics, forms, or tracking pixels. Fonts and images load locally; our hosting provider may retain routine request logs. Optional referral links are explained in our website privacy details.
Made to be useful
Now available on the App Store · U.S. price $2.99 · One-time purchase
Beyond the scan
Pair observation with practical habits: respect others’ privacy, protect sensitive conversations, and use trusted connections. A VPN can help with network traffic; it cannot stop a nearby camera from recording.
Build better privacy habitsIndependent development
Enjoying Spectra? Support the work behind it.
An optional contribution is a way to show your appreciation for Spectra and support device research, real-world testing, and thoughtful improvements.
Your purchase already supports our work. App updates are included—no additional payment is required.
Optional one-time contribution · Checkout hosted by Stripe.
