Conversation

If I hypothetically wanted to run a non-web-exposed server (e.g. on an IP4 LAN, behind NAT) and wanted to be able to send stuff (text, images) to it from my phone to add to lists for processing, what is a good way to have a mailbox that it can pick up from a php API?

I only want to email from myemail@ymail or gmail.com to <mailbox> then use a crontab+bash or php script on the private server to collect mail out of <mailbox> every hour or something.

What is something low-maintenance and low-overhead you could use for the mailbox?