Image and copy,
in the messages app.

Yes. SMS, MMS, EDM, and WhatsApp all support send-at date and time in the dashboard — appointment reminders, event countdowns, flash offers, newsletters, and template broadcasts go out at the right moment. The API accepts scheduling parameters (e.g. scheduled_at) for system-driven sends. Edit or cancel before the window; SMS and MMS fire DLR after send; WhatsApp reports delivery and read; email has delivery and open tracking.

Usually yes — as long as you send to their registered mobile number (e.g. a client's +852 HK line), the message reaches their home carrier first, then forwards abroad via international roaming. SMS and MMS work differently — delivery and cost are not the same, so we split them below.

Cost: sender (you) — Sending to +852 does not add a separate "roaming send" surcharge because the recipient happens to be abroad; you pay our standard SMS / MMS rate. If they have moved and you send to their new local number, that region's rate applies (see "Can one account send to other regions?").

Cost: recipient — Whether they pay anything depends on their own mobile plan and roaming terms; we cannot guarantee on behalf of their carrier. We recommend telling end users to check roaming SMS / data charges with their provider before travel.

SMS (text only)
• Delivery: OTP and transactional messages usually arrive; occasional delays of seconds to a few minutes. Plain text does not require mobile data to be on.
• Recipient cost: Some plans include free incoming SMS on roaming; others charge per message — carrier-dependent.
• When it fails: Roaming disabled, weak signal, phone off / airplane mode, or some roaming carriers filtering marketing SMS.

MMS (multimedia message)
• Delivery: Less reliable on roaming than SMS — use SMS for time-critical notices.
• MMS with an image: A notification may arrive first, but downloading the image usually needs mobile data (MMS retrieval often does not work over Wi‑Fi alone). If data roaming is enabled, opening or auto-downloading the image can trigger roaming data charges — even when "receiving the message" is free on their plan, loading the image may still bill data.
• Text-only MMS (no image): Still MMS on the network; the phone must fetch a small payload — far less data than image MMS. It may need a brief mobile-data connection but rarely causes noticeable roaming data fees; delivery is still less dependable than SMS.

For both SMS and MMS we submit to the home carrier as normal and report carrier-side status honestly via DLR.

Sender ID is the sender name shown on the recipient's phone. In the 852 region there are two common forms: an alphanumeric Sender ID (e.g. YourBrand), typically live within one business day; and an OFCA # Sender ID under Hong Kong's SMS Sender Registration Scheme (e.g. #YourBank) — only businesses vetted and registered with OFCA and the Communications Authority may use the # prefix.

What's the difference? Alphanumeric shows your brand name; # additionally signals to recipients that the sender is officially registered, helping distinguish legitimate messages from phishing — they see #YourBank instead of plain YourBank.

Why does it matter? For finance and high-trust use cases, # Sender ID is becoming a baseline customer expectation. We handle alphanumeric and OFCA # registration, content review, and naming advice — you just provide company details.

Images support JPG / JPEG, PNG, and GIF — we strongly recommend JPG / JPEG for the smallest file size and fastest delivery. Each image must be no larger than 800 × 800 px.

Many teams assume MMS has "almost no text limit" — carriers actually cap the total MMS payload (text + image combined) at 230 KB. Plain text is tiny: about 30 KB for 10,000 Traditional Chinese characters, so copy can run long — but whatever is left of the 230 KB budget goes to the image. Example: 30 KB of text + a 200 KB image = 230 KB at the limit. Preview total size in the dashboard before send to avoid rejections.

Yes. MMS travels via direct carrier routes into the phone's native messages inbox — not email, not an in-app channel. Every MMS gets a delivery report; failures include a reason, with no pretending "accepted" equals "delivered". Your dashboard shows the state of every campaign message.

After signup you can configure the API quickly and send a test SMS or MMS from the admin dashboard in one click. Most teams start integration with our 4-language sample code right away. A named integration engineer is assigned within 24 hours when you need help with blockers.

Yes. That's our full submission pledge: every send request your API makes that we accept is submitted to the carrier network — counts you can reconcile against your own request logs in the dashboard, with exports for audit. Whether the carrier then delivers to the handset is reported honestly via DLR; we don't silently drop or shave volume before it leaves our platform. See the Honest Delivery Standard.

Yes — and we're happy to explain what they are. A grey route is a cheaper third-party hop that disguises sender identity. Carriers can detect and block them, hurting delivery rates silently. Our SMS and MMS routes are SS7-direct with the carrier, which costs more per message but produces honest DLRs.