Promotional sms is for commercial purpose, mean if u have product/service , then you can advertise using/sending bulk sms to any mobile number in india, but transactional sms is for informational purpose, mean, if u have scool, you want to send attendence to parents of your school children, then you can use transactional sms.

Promotional sms with sender id, means, in the recipient mobile show, your company/bran name with 6 English letters, promotional sms without sender id, means, in the recipient mobile show only numeric sender id .

Voice calls means, you can record, your voice in 30 seconds, upload and send how many people u want listen your voice.

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