Updated October 29, 2026 · Version 2026-10-29.2

Setup and current limits

Callback is in development. Purchase and live messaging are unavailable. Paid-service policies below describe the approved planned subscription; they do not activate billing or unverified app controls.

Before connecting

Callback is a Windows development app. The public website does not provide a download, live setup service or subscription checkout. The customer-owned provider integration is development code; real activation and carrier testing remain pending. No provider account, number or credentials are configured by visiting this page.

Provider requirements

The integration uses one customer-owned Twilio US1 account and SMS-capable number per local workspace. You must confirm number eligibility, applicable sender registration, account permissions and consent for the actual messages. Twilio number, usage, registration and carrier costs are separate from Callback. Existing mobile-number compatibility is not guaranteed.

Local operation

Manual owner-written replies and retained history sync depend on a connected native app. Polling runs while open; closing the app delays local sync and follow-up visibility. Initial history sync covers the last 30 days. Catch-up after reopening depends on Twilio still retaining the history. The app does not operate as an always-on missed-call answering service, automatic booking service or calendar integration.

Protect your data

Ordinary business records and drafts are stored locally without application-level encryption. Protect your Windows account and disk, and keep readable exports/backups secure. Native provider credentials use an OS-backed encrypted vault; disconnect removes that saved key but does not revoke it at Twilio or erase records. MMS media transport is not supported.

Review before use

Read Terms and license, Privacy and data, Messaging responsibilities, Refunds and cancellation and billing disclosures. Billing is disabled. Production subscription verification, cancellation/refunds and trusted paid-period enforcement remain launch gates. Confirmed local deletion is implemented in the private development build, not publicly released or installed into the stable app. It requires a fresh matching verified export, typed confirmation, disconnected Twilio and resolved uncertain sends. It retains settings, legal/subscription audit and pseudonymous opt-out/history/retry safeguards; exports, backups and provider copies remain. See the privacy notice for the full scope. No policy link or page visit activates messaging or creates an agreement.