The short version
Sightline is developed and published by Ethoseen LLC, an Oregon limited liability company. It is a desktop application with a paired iPhone companion. It saves student records to a file on your Mac. During an untethered observation, observation data stays on the paired phone until the devices reunite. We don't operate a server that receives that data, and we never hold a copy. Deleting local data does not leave a vendor-held copy to sync or restore.
The app is not fully offline, and we won't pretend otherwise. It validates your license (and issues your free trial if you start one), checks for updates, downloads the AI model the first time you use it, and, if you turn them on, sends product-usage analytics and crash reports. The next section lists every one of those connections, what each sends, and where. The app-level payloads are configured to exclude student names, notes, and observations.
When an untethered observation is on your phone
An untethered observation can remain on your paired iPhone until it reunites with your Mac, potentially for days. When the devices reconnect, Sightline transfers the observation to the Mac over their paired, encrypted local Bluetooth link. The phone removes its copy only after the Mac has stored the observation and confirmed receipt.
Those files are encrypted at rest while the phone is powered off or before its first unlock after boot. This is not per-lock protection: after that first unlock, Sightline can continue appending observation events while the phone is locked in your pocket.
The AI runs on your machine
Sightline's AI features, narrative report drafting, pattern detection, and FBA hypothesis suggestions, run on an open-weights model that executes entirely on your Mac. You download the model once, a few gigabytes, then every draft is generated there. Observation data is not sent to a cloud AI provider, and there's no API key to add.
No student data is sent to a cloud AI provider. The one-time model download requests only the model file. Drafts are then generated on your Mac, with no observation data sent back over the internet.
What connects to the internet
Here is every connection Sightline makes. Open Little Snitch or any network monitor, and this is the complete list. The automatic connections do not send observation data. The feedback connection sends only the text you enter and, if you provide it, your email address.
- License validation api.keygen.shConfirms your license is valid and ties it to this device. Sends your license key and an anonymous machine fingerprint. No student data.
- Trial issuance license.sight-line.appOnly when you start the free trial. Sends a one-way hashed device identifier, derived from hardware and not reversible to you or your students, plus the app version, so the same machine can't take unlimited trials. No student data.
- License heartbeat heartbeat.sight-line.appOn each launch, a licensed copy pings to confirm it is still active. Sends your license key, the same anonymous machine fingerprint, the app version, and the date you first activated. No student data.
- Feedback you send feedback.sight-line.appOnly when you open the feedback form and submit it. Sends the text you wrote and, if you choose to provide it, your email address. Nothing is sent unless you click submit.
- App updates updates.sight-line.appChecks whether a newer, signed version exists and fetches it if so. Sends your current app version and platform to pick the right download. A licensed install also sends its license key, and a Free tier or post-trial install also sends an updater passport token and the same anonymous machine fingerprint. No student data.
- AI model download huggingface.co models.sight-line.appA one-time download of the on-device AI model, at your direction. The base model is a plain file request to Hugging Face's CDN, a third party that, like any website, sees your IP address. If your license includes a tuned model, that file comes from our own CDN and the request carries your license key so it can confirm you're entitled to it. Neither request sends student data.
- Optional usage analytics us.i.posthog.comYou choose on first launch, and it stays off unless you turn it on. When on, it records which screens and features get used, filtered through a fixed allowlist that excludes names, notes, and observations. You can change it any time in Settings.
- Crash and error reports sentry.io (US region)Off unless you turn it on. When on, a crash or error sends a diagnostic report, what failed and the technical stack trace, scrubbed of names, notes, and observations, so we can fix the bug. You can turn it off any time in Settings.
Architecture
FERPA-compliant student data handling
Sightline is designed and operated for FERPA-compliant handling of education records. Student records remain on school-controlled devices, and Sightline's automatic network connections do not carry observation records. The feedback form sends only the text you choose to enter and, if you provide it, your email address.
- We don't operate servers for storing or processing student records
- We don't require accounts, so there's no profile or user record on our side
- All exports (PDFs, CSVs) are generated locally on your Mac
- The AI model runs on your Mac; observations are never transmitted to a cloud provider for drafting
- Usage analytics and crash reports, when you enable them, use fixed allowlists and scrubbing configured to exclude names, notes, and observation content
Bottom line: for the data that matters, your students' records, Sightline behaves like a local spreadsheet. The records stay in a file on your Mac; untethered observation data can wait on your paired phone until its local transfer is confirmed. Sightline's automatic connections carry neither. The feedback form sends only the text and optional email address you choose to submit.
Is Sightline FERPA compliant?
Yes. Sightline uses FERPA-compliant student data handling. Observation records are stored locally on the practitioner's device, not in a Sightline cloud database. AI processing runs on-device, and Sightline does not use student records for advertising, model training, or resale.
Schools and districts remain responsible for approving the software and managing device access, consent, retention, exports, and disclosures under their own policies and applicable law.
How it works under the hood
Built with Tauri
Sightline uses Tauri 2, a modern framework for building lightweight native desktop apps. The result is a fast, small application that feels like it belongs on your system, not in your browser.
Your data, your files
On the Mac, observations are stored in a local SQLite database. Untethered observation data is held locally on the paired phone until its confirmed transfer, as described above. You can back up, move, or delete the Mac database. There's no cloud sync and no vendor lock-in. Sightline's automatic server connections handle licensing, updates, the model download, and the optional analytics and crash reports; none receive observation data. The feedback server receives only the text and optional email address you choose to send.