SMS

SMS in Mersal covers two very different ways of sending a text message: through a professional SMS API provider, or through a physical SIM card in an Android phone you already own. You can use either, or both, depending on the account.

Sending options

• External SMS API providers — connect credentials for Twilio, Vonage, or any other HTTP-based SMS provider. This is the route for production-scale sending with provider-level delivery guarantees and reporting.
• Android SIM Gateway — pair an Android phone running the Mersal bridge app, and Mersal routes SMS out through that phone's SIM card. There's no provider account or per-message API cost involved — you're sending through a real SIM the same way you would by hand, just automated. It's a practical way to start sending SMS immediately, or to run a secondary channel alongside a provider.

Both options plug into the same SMS sending flows — the underlying gateway is just a setting, not a different feature. See Gateways Overview for how gateways are connected and managed across all channels.

Message types

• Plain — standard GSM-encoded text.
• Unicode — for messages containing Arabic, emoji, or other characters outside the basic GSM character set.
• Flash — messages that display directly on the recipient's lock screen without being saved to their inbox.

Single send vs. campaigns

You can send SMS two ways:

• Single message — pick a contact and send one SMS directly, useful for one-off or transactional messages.
• Campaign — send to an entire group of contacts at once, either as a dedicated SMS campaign or as one channel within a unified campaign alongside WhatsApp and Email.

Rate limits

Every SMS gateway has rate-limit presets that cap how fast messages actually go out — per-minute, per-hour, and per-day limits. These aren't just informational: they control the real sending pace, which matters both for staying within a provider's own limits and for keeping an Android SIM gateway sending at a safe, sustainable rate.

Sending programmatically

To send SMS from your own backend instead of the dashboard, see the SMS Send API reference.