In-App Voice calling
Have your customers at hello with flexible in-app voice calling
Build trust and meaningful customer relationships while keeping costs down, and scale as you go with our flexible in-app calling solution. With our scalable in-app voice calling SDK, you’ll have them at hello!
Join over 150,000 businesses, including 8 of the 10 largest tech companies in the world.
Hassle-free, scalable calling experience
Level up user experience
Connect with confidence
Future-proof your business
Cost-effective, high-quality calling
Everyone loves crisp, high-quality calls, and now you can have them all the time, both app-to-app and app-to-phone. Built with users in mind, our APIs and SDKs are scalable, flexible, and super easy to use.
We use our industry-leading infrastructure, enterprise-grade platform, and data-optimized routing to power calls across the globe. Give your calls the quality they deserve!
“Sinch gives us a mix of fantastic quality and solid reliability that the Rebtel app depends on.”
“Carbonapps needed a reliable app-to-app voice and video calling solution for their yabChat Messenger app – they turned to Sinch for the answer.
We opted for Sinch due to the quality, ease of integration and excellent customer support.”
“Sinch In-App Voice Calling satisfies the needs of Cuban people who don’t have an internet connection and want to stay in touch with friends and family outside of Cuba. The connection is very convenient – it’s great quality!”
Smooth real-time communication
Easily integrate voice to your app using our SDKs for iOS, Android, and Javascript, and expand globally without expensive telecom infrastructure.
Identify callers and add context to calls with metadata for a smoother customer experience. While you’re at it, make the most of our WebRTC – we’ve spent the last ten years fine-tuning it to perfection, just for you!
$client = new Clx\Xms\Client("{spid}", "{token}");
$batchParams = new \Clx\Xms\Api\MtBatchTextSmsCreate();
$batchParams->setSender("12345");
$batchParams->setRecipients(["46123123123"]);
$batchParams->setBody("Hello, World!");
try {
$result = $client->createTextBatch($batchParams);
echo("Successfully sent batch " . $result->getBatchId());
} catch (\Clx\Xms\ApiException $ex) {
echo("Failed to communicate with XMS: " . $ex->getMessage() . "\n");
}
const targetPosition =
element.getBoundingClientRect().top + window.pageYOffset + offset
const startPosition = window.pageYOffset
const distance = targetPosition - startPosition
// Initialize a start time for the animation
let startTime = null
Build a killer call experience
Build your app, and start making calls in minutes! Use our iOS, Android, or JavaScript SDKs combined with our sample app code and documentation to get started today.
Connect with customers around the world in seconds
Cross-platform support
Peer-to-peer communication
Global reach
Easy integration
Pay as you go
End-to-end encryption
Enterprise-grade reliability
Got questions? We’ve got answers!
Sinch In-App Voice Calling uses the WebRTC framework – the most frequently used voice and video calling technology for IP-based communication. WebRTC combines multiple technologies to ensure the best call quality around.
Our technology supports multiple protocols, but we mostly use OPUS. It’s a flexible auto-codec that adapts voice quality to suit network quality – a good connection results in HD voice quality.
The video codec we mostly use is VP8.
Sinch powers all kinds of applications, from MVP prototypes to successful and widely used applications. Our services scale on demand and offer high availability at all times.
It depends on the type of calls – voice app-to-app, video app-to-app, or app-to-phone. Need more details? Contact us to get a copy of our guide!
The Sinch SDK uses P2P for the voice stream when possible. We use the ICE standard for NAT traversal. If a P2P channel isn’t possible – for example when both sides are behind a symmetric NAT – the voice channel will fall back to Sinch media proxies. 70-75% of calls made will go over P2P, and 25-30% will go through servers due to firewall restrictions.
Related products
Voice API
In-App Video Calling
Number Masking
STIR/SHAKEN
What are you waiting for?
Start building conversations now!