I am developing a React Native application for IOS and Android. I am using Django for my backend and aws rds for my database. It is deployed on AWS Lambda and both my lambdas and my rds are in a VPC. Everything worked well except for push notifications as they require my lambda functions to communicate to the public internet.
One way would be to create a NAT Gateway to allow that communication, but a NAT Gateway is quite costly.
I am thinking of another way which involves AWS Simple Notification Services (SNS). If I integrate that to my Django app, would the lambda functions be able to communicate with AWS SNS without requiring a NAT Gateway?