A Voice SMS Service provider  is a company that offers technology to convert text messages into voice messages and deliver them to a recipient's phone.

These providers typically use communication APIs (application programming interfaces) that allow businesses to integrate voice SMS functionality into their applications or software.

Here's a breakdown of how it works:

1. You send a text message through the provider's platform. 2. The platform converts the text message into a voice recording using text-to-speech technology. 3. The voice recording is then delivered to the recipient's phone as a voicemail or a similar service.

There are several reasons why a business might use a Voice SMS service:

1 - For people who prefer to listen to messages: Some people find it easier to listen to a message than to read it on their phone.

2 - For accessibility: Voice SMS can be helpful for people with visual impairments or who have difficulty reading.

3 - To deliver important information: For critical messages, a voice message can ensure that the recipient receives and listens to the information.