Calla: Block Spam Calls

Since 17 October 2026, Spanish law requires every company that calls you to sell something to use a number starting with 400. Calla blocks that whole prefix, a million numbers, so those calls never ring. It is free and has no ads.

WHAT CALLA BLOCKS
• Every sales call from the 400 prefix (Spanish Law 10/2025)
• Any number you want to block, from Spain or abroad
• With Pro: whole prefixes and the community spam list

YOU WON’T MISS IMPORTANT CALLS
• Customer service from your bank, energy company or doctor cannot use 400
• Exceptions: numbers that must always ring
• Blocking 400 can be turned off with one tap

TOGETHER, LESS SPAM
• Report the numbers that bother you: advertising, scam, survey, robot
• Numbers reported by several people join the community list

PRIVATE
• No account and no ads
• Calla never reads your contacts
• The blocking happens on your phone; your calls are not sent anywhere

HOW IT WORKS
• iPhone: switch Calla on in Settings › Apps › Phone › Call Blocking & Identification; the phone blocks the calls itself
• Android 10 or later: choose Calla as your caller ID & spam app, and see every blocked call in its history

Blocking the 400 prefix is and will always be free. Calla Pro is a one-time purchase (not a subscription): community spam list, unlimited blocked numbers and blocking whole prefixes. Calla cannot block hidden numbers, and calls from abroad or from companies breaking the law do not use 400.

OFFICIAL SOURCES
• Law 10/2025 on customer service (Spanish Official Gazette, BOE): https://www.boe.es/buscar/act.php?id=BOE-A-2025-26698
• Resolution of 14 April 2026: the 400 range for sales calls (BOE): https://www.boe.es/diario_boe/txt.php?id=BOE-A-2026-8409

Calla is an independent app made by Basel1905 Studio. It is not an official app and is not affiliated with, endorsed by or representing the Government of Spain or any public body.

Terms: https://basel1905.com/calla/terms.html
Privacy: https://basel1905.com/calla/privacy.html

Recent changes:
First release.