Simon-RedditAccount

Can't you just install this type of app to your phone or pc?

For one instance of app, it's possible to install it onto a single machine.

Things get tricky when you want to access the data from multiple devices. Even trickier, when several people want to access it. After a certain point, it's easier to have a "cloud" solution. And since "cloud" is just somebody's else computer, why not make this a computer YOU own?

Lack of time or interest (or both) in: managing local DNS, using .home.arpa and running own CA.

It's tricky (especially running your own CA in a proper way), and not everyone wants to do it. Also, running it in a proper way it requires knowledge, and some people don't have it...

Actually, distribution of your root CA certificate is not that difficult.

NOTE: this addresses strictly OP's question about LAN-only access. External access or varying devices used to access is a completely different story.

• Google Workspace. Not the cheapest, and also by Google (although they claim they don't mine as much data from business accounts)
• Zoho, $1.25/mo
• iCloud+, $0.99/mo, but a bit limited (don't remember whether they have catch-all etc).

Do you monitor network traffic?

Generally, no. But I seriously restrict container networking, most of my containers are unable to reach internet, unless absolutely necessary. Also, my firewall is not super-restrictive, but it is different from defaults :)

Sometimes I do some monitoring though.

Privacy, Education, Being Cool. Also, there are some services that are not available commercially.

Possible - yes.

Do you want it? Probably, no. Especially, SMTP. Better use something like Zeptomail (cheapest) for delivery.

You can still self-host the receiver.

Mandatory do-not-self-host-at-home notice: custom domain at skiff.com is free, iCloud+ Mail is $0.99 and Zoho is $1.25/mo.

Yes, there are risks:

• First, updates can break things. Already explained here.
• Second, exposing Docker socket to Watchtower means you have to trust it ultimately. Any vulnerability in WT can lead to whole system compromise.

Personally, I use DIUN. It just sends me notifications about available updates. I update things manually later. My system is pretty well isolated from outside world, so no need to hurry.
On a VPS, I would prefer a different approach though.

• good-looking domains instead of IPs
• tons of subdomains instead of ports
• universally recognized TLS certs via Let's Encrypt. DNS challenges are the way to go - you don't even have to expose your HTTP server
• dynamic DNS, again available via API
• [email protected] (better not to self-host, but to use an email provider)