London Daily

Focus on the big picture.
Wednesday, Jul 30, 2025

What is Signal (WhatsApp secure-alternative), and why is it suddenly popular in Hong Kong?

What is Signal (WhatsApp secure-alternative), and why is it suddenly popular in Hong Kong?

The messaging app saw a surge in downloads after a new national security law came into force. End-to-end encryption is a key feature of the privacy-conscious app

Signal is the new app of the moment in Hong Kong.

Since June 30, the city’s residents have been flocking to the messaging app, driving it to the top spot on both Apple’s App Store and Google Play. It also saw a surge in American users who organised and participated in Black Lives Matter protests nationwide.

Here’s what you need to know about the hot privacy-conscious app.


Encryption for everyone, not just the tech-savvy

Signal was created by American cryptographer and Twitter’s former head of security Moxie Marlinspike. His goal was to build an easy-to-use digital tool that helps ordinary people keep their communications secure.

The free app is developed by a non-profit organisation supported entirely by grants and donations. Over the years, it has received close to US$3 million from the Open Technology Fund run by the US Agency for Global Media, the government agency that also oversees Voice of America.

Signal boasts millions of daily users, with US whistle-blower Edward Snowden among them. The European Commission also told its staff to switch to Signal earlier this year.

The app has already been blocked in some countries such as Egypt, Oman, Qatar and United Arab Emirates. Surprisingly, it still works in mainland China… for now.


Why are Hongkongers turning to Signal?

Late at night on June 30, Hong Kong adopted a new security law that went into effect the next day. Crafted by Beijing, the rules grant local authorities sweeping powers to crack down on acts of secession, subversion, terrorism and collusion with foreign forces. Secret surveillance can be approved by the city’s leader.

Downloads of Signal surged immediately after the legislation was unveiled. Residents told the South China Morning Post that they started taking various cybersecurity measures to protect their privacy. Some people quit social media. Others are using VPNs – software that allows users to hide the origin of their traffic by encrypting and re-routing it.


Is Signal really secure?

Signal uses end-to-end encryption, just like WhatsApp and iMessage. That means when you send a message, it’s scrambled into a series of unreadable codes that make no sense to anyone who intercepts it during transmission. Only the intended recipient has the key to decrypt and read the message. Hackers, police, your phone company and even Signal itself are all unable to see the content of whatever you send.

The code behind Signal is open source, meaning researchers are free to examine for flaws. It’s widely held up as an example of sound encryption. WhatsApp’s encryption is even based on the Signal Protocol.

Signal also famously encrypts metadata that other messengers like WhatsApp don’t. So the organisation can’t even see who is talking to whom or when.

In 2016, US prosecutors issued a federal subpoena to the group behind Signal, requesting data on two suspects using the app. Authorities sought information that included names, phone numbers, email addresses and IP logs. None of the data was turned over, according to court filings published by the American Civil Liberties Union.


Can’t I just use other end-to-end encrypted messaging apps?

You can, but there are some features that make Signal unique.

For one, Signal conversations are only stored locally on devices. This contrasts with WhatsApp, for example, which lets users back up their chat records on iCloud or Google Drive, neither of which adopt end-to-end encryption for all data. Apple, however, has stressed that only the company itself holds the encryption key to iCloud data.

Signal also offers a few options for additional layers of protection. A photo or video can be set to automatically delete after it’s been viewed. You can also turn on disappearing messages, which will erase messages after a set period of time – anywhere from five seconds to a week.

Signal also recently introduced a blur feature in the image editor. This hides the faces of people shown in a photo with a fuzzy box.


I use Signal, so I can relax, right?

All technology has limits – even Signal.

As much as you value privacy, the people you message can always take screenshots of your conversations or save images you sent without telling you. Also, if their phones are compromised, any data on their device – including your chat history and phone number – could also be exposed.

Newsletter

Related Articles

0:00
0:00
Close
Former Judge Charged After Drunk Driving Crash Kills Comedian in Brazil
Jeff Bezos hasn’t paid a dollar in taxes for decades. He makes billions and pays $0 in taxes, LEGALLY
China Increases Use of Exit Bans Amid Rising U.S. Tensions
IMF Upgrades Global Growth Forecast as Weaker Dollar Supports Outlook
Procter & Gamble to Raise U.S. Prices to Offset One‑Billion‑Dollar Tariff Cost
House Republicans Move to Defund OECD Over Global Tax Dispute
Botswana Seeks Controlling Stake in De Beers as Anglo American Prepares Exit
Trump Administration Proposes Repeal of Obama‑Era Endangerment Finding, Dismantling Regulatory Basis for CO₂ Emissions Limits
France Opens Criminal Investigation into X Over Algorithm Manipulation Allegations
A family has been arrested in the UK for displaying the British flag
Mel Gibson refuses to work with Robert De Niro, saying, "Keep that woke clown away from me."
Trump Steamrolls EU in Landmark Trade Win: US–EU Trade Deal Imposes 15% Tariff on European Imports
ChatGPT CEO Sam Altman says people share personal info with ChatGPT but don’t know chats can be used as court evidence in legal cases.
The British propaganda channel BBC News lies again.
Deputy attorney general's second day of meeting with Ghislaine Maxwell has concluded
Controversial March in Switzerland Features Men Dressed in Nazi Uniforms
Politics is a good business: Barack Obama’s Reported Net Worth Growth, 1990–2025
Thai Civilian Death Toll Rises to 12 in Cambodian Cross-Border Attacks
TSUNAMI: Trump Just Crossed the Rubicon—And There’s No Turning Back
Over 120 Criminal Cases Dismissed in Boston Amid Public Defender Shortage
UN's Top Court Declares Environmental Protection a Legal Obligation Under International Law
"Crazy Thing": OpenAI's Sam Altman Warns Of AI Voice Fraud Crisis In Banking
The Podcaster Who Accidentally Revealed He Earns Over $10 Million a Year
Trump Announces $550 Billion Japanese Investment and New Trade Agreements with Indonesia and the Philippines
US Treasury Secretary Calls for Institutional Review of Federal Reserve Amid AI‑Driven Growth Expectations
UK Government Considers Dropping Demand for Apple Encryption Backdoor
Severe Flooding in South Korea Claims Lives Amid Ongoing Rescue Operations
Japanese Man Discovers Family Connection Through DNA Testing After Decades of Separation
Russia Signals Openness to Ukraine Peace Talks Amid Escalating Drone Warfare
Switzerland Implements Ban on Mammography Screening
Japanese Prime Minister Vows to Stay After Coalition Loses Upper House Majority
Pogacar Extends Dominance with Stage Fifteen Triumph at Tour de France
CEO Resigns Amid Controversy Over Relationship with HR Executive
Man Dies After Being Pulled Into MRI Machine Due to Metal Chain in New York Clinic
NVIDIA Achieves $4 Trillion Valuation Amid AI Demand
US Revokes Visas of Brazilian Corrupted Judges Amid Fake Bolsonaro Investigation
U.S. Congress Approves Rescissions Act Cutting Federal Funding for NPR and PBS
North Korea Restricts Foreign Tourist Access to New Seaside Resort
Brazil's Supreme Court Imposes Radical Restrictions on Former President Bolsonaro
Centrist Criticism of von der Leyen Resurfaces as she Survives EU Confidence Vote
Judge Criticizes DOJ Over Secrecy in Dropping Charges Against Gang Leader
Apple Closes $16.5 Billion Tax Dispute With Ireland
Von der Leyen Faces Setback Over €2 Trillion EU Budget Proposal
UK and Germany Collaborate on Global Military Equipment Sales
Trump Plans Over 10% Tariffs on African and Caribbean Nations
Flying Taxi CEO Reclaims Billionaire Status After Stock Surge
Epstein Files Deepen Republican Party Divide
Zuckerberg Faces $8 Billion Privacy Lawsuit From Meta Shareholders
FIFA Pressured to Rethink World Cup Calendar Due to Climate Change
SpaceX Nears $400 Billion Valuation With New Share Sale
×