Insights & practical guides

SMS vs MMS vs WhatsApp: OTP, marketing, support, cost, and compliance in one view. When Hong Kong businesses use which channel, shared suppression lists, and conversion tracking.

Use teams to separate business units, departments and agencies inside one account so each only sees its own lists and campaigns, then optionally add a maker-checker step where operators submit and reviewers approve. Five roles, the isolation rules, and four worked scenarios.

SMS is the text-messaging service built into every mobile network. How it works, the 160 / 70 character limits, how it is billed, how it differs from MMS, why one-time passcodes still rely on it, and the sending rules in Hong Kong and Taiwan.

WhatsApp Business API Hong Kong: Business verification, template approval, 24-hour conversation window, opt-in and unsubscribe. When to use WhatsApp vs SMS, and unified suppression lists on one platform.

Turn an FAQ sheet into a WhatsApp customer service bot: merge duplicate questions, build three-level list menus, add the same three buttons after every answer, collect the order number before handing off, and stay within Meta's interactive message limits.

"Submitted" is not "delivered". A breakdown of the two-tier SMS reporting model, what every status code means, and how UNDELIV, EXPIRED and REJECTD should each be handled.

What a grey route is, how to spot one, and what it actually costs you in deliverability, sender name integrity, DLR honesty and regulatory exposure. With four tests you can run yourself.

How Hong Kong businesses obtain a dedicated "#" sender name under the OFCA SMS sender-registration scheme — naming rules, documents required, the secure network requirement, and what gets applications bounced.

OTP looks like "send a number". Expiry, resend windows, rate limiting, route separation and AIT fraud defence all bite when they are wrong. The six we see most often in production integrations.

Why 70 Chinese characters bills as two messages. GSM-7 versus UCS-2, the 160/153 and 70/67 segmentation rules, and how to reconcile your real billed count with the usage report API.

Read before sending promotional SMS or MMS to Hong Kong numbers. Sender information, unsubscribe facilities, the 10-working-day rule, the three Do-not-call Registers — the ordinance's duties and a checklist you can actually run.

Why does SMS fail to arrive even when the API returned success? The real causes are more numerous than you would expect — from carrier filtering and SIM status to grey-route forwarding.

Marketing email landing in spam? How mailbox providers decide in three layers — authentication, sender reputation, content — plus how to diagnose where you stand, how to recover once you are flagged, and the unsubscribe rules in the US, UK, Hong Kong and Taiwan.

Clients keep asking whether email still works. When they ask, they are usually going on their own reading habits rather than genuinely dismissing what email does. So — for marketing purposes, does email actually deliver?

How phishing SMS works, how Hong Kong's OFCA sender-registration scheme (# Sender ID) helps counter it, and how businesses should protect their brand and their customers.