- Heroku hosting

- Cloudflare free "reverse proxy" to use https on custom domain (Heroku won't do that for free)

- ImprovMX email forwarding, as for sending, you can abuse Gmail (or likely any other email service), and setup DKIM signing to remove the "via gmail.com" mark and have your emails trusted

- freenom.com free domains

- Heroku postgres and redis, if you run into the 10k rows limit, ElephantSQL (i don't remember the limitations there) or setup a postgres server on GCP compute engine