I have gone through your requirements and understood perfectly. I have 10 years of experience in Mobile apps Android , iPhone, Native, Flutter, PhoneGap, IONIC, React Native and Backend Admin panel, API and professionLagi
Please find the below points for my experience:
- Install and configure kannel SMS gateway (SMSbox - SQLbox - OpenSMPP - SMPPKannelBox "SMPP server with Licence" ) with your operators or aggregators.
- Design SMLagi