I am developing an app that allows users to send SMS messages in bulk.
I started working with Twilio, but after I started interfacing with their API I learned that they don't support custom phone numbers for sending SMS messages (like a personal phone number.)
I mean, if I want the users of the app to be able to send SMS messages in bulk and the sender ID is a personal phone number, Twilio does not allow it.
I'm looking for a 3rd party system to send bulk sms messages with a custom sender ID like the user's phone number.