Sentinela — Offline Blocker

Sierra Tecnologia LTDA

About this app

Your phone rings. It's another number you don't recognize.

A debt-collection robot. Someone pretending to be your bank. A cold sales call. A survey at 8am on a Saturday. You pick up because you're afraid of missing something important — and all you lose is your time, again.

Sentinela exists to end that, using one rule:

IF IT'S NOT IN YOUR CONTACTS OR YOUR PERSONAL LIST, IT DOESN'T INTERRUPT YOU.

No ring. No vibration. No call screen. No missed-call alert.

🔒 PRIVACY THAT ISN'T JUST MARKETING COPY

Sentinela ships without the internet permission. This isn't a promise that "we don't use it": the app is technically incapable of sending anything anywhere.

• Zero telemetry, zero ads, zero accounts to create
• Your contacts are read in memory only, at the moment of the call — names, photos and numbers are never stored and never sent
• Your full number never appears in a log or a notification, only masked: +1 555 ***-1234
• Your data is excluded from Android's automatic backup
• Works in airplane mode. Works with no signal. Works forever, offline
• Open source — auditable line by line

⚙️ YOU DECIDE, NOT AN ALGORITHM

No cloud spam database choosing for you. You set the policy for each origin, and each one accepts Ring, Silence, Block or Never Silence:

• Contacts in your address book → Ring (default)
• Your personal list → Never Silence (default)
• Numbers outside contacts → Block (default)

⭐ PERSONAL LIST

Your doctor, your kid's school, the delivery driver, that one number you're waiting on today. Add it, search it, edit it. Export it to a file and import it back when you switch phones — the backup is yours and it stays with you.

📋 OPTIONAL HISTORY

See what was stopped, when, and why — in plain language, not an internal code. Mark a call as legitimate and send it to your personal list with one tap. Filter by period and by decision. Choose retention: never keep, 7, 30, 90 days, or clear it by hand. Turned off, nothing is written at all.

📞 OPTIONAL DIALER MODE

If you want, Sentinela becomes your phone app: a clean in-call screen, a dialer with live number formatting, call timer, mute, speaker and touch-tone keypad. Your policies then apply to contacts too. It's opt-in, reversible at any time from Android settings, and the app works perfectly well without it.

🎨 BUILT THE WAY IT SHOULD BE

Material 3, dark theme and dynamic colors from your wallpaper. No ads, no "premium tier", no subscription wall, no dark pattern trying to make you tap the wrong thing.

🚫 WHAT SENTINELA DOES NOT DO

We'd rather tell you before you install:

• It does not filter WhatsApp, Telegram or other app calls — Android does not hand those calls to screening apps
• It does not identify who's calling: there is no spam database here, and that's on purpose
• It does not erase the blocked call from your system phone app's call log — Android only allows that for carrier apps. The call won't ring or notify you, but the entry stays there
• It does not bypass Android's Do Not Disturb
• It does not record calls, read SMS, or read your call log

📱 Requires Android 10 or newer — the system's own requirement for the call screening role.

Sentinela. The silence you configured.

Offline call blocker and spam filter. Protect privacy, stop robocalls, and block unknown numbers with no ads.

Bloqueador de llamadas offline y filtro de spam. Bloquea números desconocidos y robocalls sin anuncios.

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Sentinela est votre bloqueur d'appels hors ligne et filtre anti-spam. Protégez votre vie privée, bloquez les numéros inconnus et les robocalls sans pub.

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