Are messages sent on Campaigns supported by all mobile phones?

Campaigns helps you reach your audience across multiple messaging channels — but compatibility depends on the channel, the device, and the recipient’s setup.

Sinch recommends that you start with SMS for guaranteed reach, then enhance your campaigns with RCS, WhatsApp or MMS depending on your audience and goals.

Here’s how each channel performs, so you can choose the best option for your campaign.

SMS — maximise your reach

SMS remains the most reliable way to connect with your audience.

• ✅ Works on virtually all mobile phones (smartphones and basic phones)
• ✅ Available worldwide across all carriers
• ✅ No internet connection required

As long as your recipients are connected to a mobile network and have not opted out, your messages can be delivered.

If your goal is maximum reach and reliability, SMS is the channel you can always depend on.

RCS — create interactive experiences

RCS takes messaging further with rich, interactive content (images, buttons, branded experiences).

• Available on compatible smartphones only
• Depends on carrier and country support

Target the right audience

With Campaigns, you can perform a capability check to identify which recipients support RCS.

• Focus on eligible users for a seamless experience
• Build your own multi-channel strategy when needed

RCS allows you to stand out and engage users with modern, app-like experiences, while staying in the native messaging app. Engage end users with conversations.

WhatsApp — engage where your customers already are

WhatsApp allows you to connect with users on one of the world’s most popular messaging apps.

• Requires recipients to:
  • Have WhatsApp installed
  • Be connected to the internet
  • Have opted in to receive your messages
• ✅ Consistent experience across devices
• ✅ High engagement on active users.

If your audience is active on WhatsApp, it’s a powerful channel to drive engagement and conversations.

MMS — enrich your messages (where available)

MMS lets you enhance your campaigns with images, videos, and rich media, adding visual impact to your messages.

Availability

• ✅ Available in United States, Canada, and Australia
• ❌ Not supported in other countries.

Compatibility

• Requires a compatible device and mobile plan
• Not supported on all phones (especially older devices).

Content considerations

• Carrier-specific file size and format limits
• Media rendering may vary depending on the device.

When you’re targeting supported countries and want to boost engagement with visual content.

What else can impact delivery?

irrespective of the channel, delivery can also be influenced by:

• Network availability
• User consent (opt-in / opt-out)
• Carrier and regulatory requirements
• Device capabilities
• Country-specific restrictions.