Vendor Portal: https://semysms.net/

About SemySMS:

Send SMS using your SIM card. SMS gateway on your phone.

SemySMS is a free SMS mailing service. Create SMS mass advertising campaigns, inform people about promotions and discounts immediately after registration! Send and receive SMS messages through the WEB interface or API, using as many Androids phones as you wish. Perform SMS mailing from your phone, easy! To start using our service, simply install SemySMS on your phone. Create your own SMS gateway!

OpenCart SMS Setup: