Cloudflare CDN (Anti DDoS and WAF)
AWS Infraestructure: AWSShield, Amazon Elasticsearch Service, AWS ELK Stack, Elasticsearc Service Index Snapshots, AWS Lambda Service, AWS SNS, AWS SES, etc.
Here is the Documented & Open Source Code as well as the API definitions following the Swagger standard.
iOS 11.0 and upper
Android 6.0 and upper
Server Laravel Elasticsearch
Code, documentation, specifications available upon request.