Further clarifications

I wanted to include a bit of rationale as to why I went with Vaultwarden instead of the official Bitwarden Open Source server, along with a note about app combability (this is a full server, providing API and application support; it's not just browser-based). To that end, I also added some clarification for novice users that the server must be externally accessible if they want to connect to it via an app from the outside world.

README.md

@@ -17,6 +17,38 @@ A hardened, self-hosted password manager appliance based on Vaultwarden. Designe
 
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+## 🤔 Why Vaultwarden Instead of Bitwarden?
+
+Vaultwarden is a lightweight, open-source implementation of the Bitwarden server API. It offers:
+
+- ✅ Full compatibility with Bitwarden official clients (web, mobile, desktop, browser extensions)
+- ✅ Extremely low system resource usage - perfect for self-hosted appliances
+- ✅ Easy customization and backup
+- ✅ No proprietary licensing restrictions
+
+Bitwarden's official server requires more complex infrastructure and higher resource consumption. Vaultwarden offers nearly identical functionality in a compact, open-source form.
+
+---
+
+## 🌐 Using Clients and Accessing Your Vault
+
+This server is compatible with the official **Bitwarden clients**, including:
+
+- 📱 **Mobile apps** (iOS, Android)
+- 🖥️ **Desktop apps** (Windows, macOS, Linux)
+- 🌐 **Browser extensions** (Chrome, Firefox, Edge, etc.)
+- 💻 **Web vault** (via this appliance's built-in web UI)
+
+To use mobile or remote clients **outside your local network**, your appliance **must be publicly accessible** (e.g., via a domain name with port 443 open and a valid SSL certificate).
+
+For example:
+- ✅ `https://vault.yourdomain.com` – accessible anywhere
+- ❌ `https://192.168.1.100` – works only on your LAN
+
+Make sure your router/firewall allows inbound HTTPS traffic and that your DNS is configured correctly if using Let's Encrypt.
+
+---
+
 ## ⚠️ **Disclaimer**
 This installer is intended **only** for use on a **dedicated appliance or virtual machine** running a clean installation of **Debian 12**.
 It will make system-wide changes, including user/group creation, file permission changes, service overrides, firewall configuration, and package installations.