Installing on Linux with apt

README.md

@@ -4,9 +4,48 @@ Snowball keeps your files on every device you own, with no cloud in between. Los
 
 Snowball is an early alpha. Keep your usual copies of anything you can't afford to lose while you try it.
 
-**[Download the latest release](https://git.tricauda.com/snowball/releases/releases/latest)**: each release has its notes, and these files:
+**[Download the latest release](https://git.tricauda.com/snowball/releases/releases/latest)**. Each release has its notes, and the files below.
 
-- **Android:** `snowball-<version>.apk`. Install it on your phone. To be offered updates, add this repository's URL to [Obtainium](https://obtainium.imranr.dev/).
-- **Linux:** `snowball-linux-x64.tar.gz`, for Ubuntu 22.04, Debian 12, Fedora 36, RHEL 9 or newer. Unpack it anywhere, then run `snowball/install.sh` once to add Snowball to your applications (`snowball/install.sh --uninstall` removes it again).
+## Android™, with Obtainium
+
+Snowball isn't in the Play Store yet. [Obtainium](https://obtainium.imranr.dev) installs it and tells you when there's an update.
+
+1. Install Obtainium (version 1.6.16 or later).
+2. In Obtainium, tap **Add app**, and for the app source URL, enter `https://git.tricauda.com/snowball/releases`.
+3. Set **Override source** to **Forgejo (Codeberg)**, then tap the **+** beside the address.
+4. Tap **Install**. If your phone asks, allow Obtainium to install apps.
+
+When there's a new version, Obtainium offers it. Tap **Update**, and your files and settings stay as they are.
+
+(Or download `snowball-<version>.apk` from a release and open it, but then you won't hear about updates.)
+
+## Linux®
+
+For Ubuntu 22.04, Debian 12, Fedora 36 or anything newer.
+
+**Ubuntu and Debian, with apt,** which also brings each update:
+
+```
+sudo curl -fsSL https://git.tricauda.com/api/packages/snowball/debian/repository.key -o /etc/apt/keyrings/snowball.asc
+echo "deb [signed-by=/etc/apt/keyrings/snowball.asc] https://git.tricauda.com/api/packages/snowball/debian stable main" | sudo tee /etc/apt/sources.list.d/snowball.list
+sudo apt update && sudo apt install snowball
+```
+
+Snowball is then in your applications, and starts whenever you log in.
+
+**Anywhere else,** from the latest release:
+
+1. Download `snowball-linux-x64.tar.gz`.
+2. Unpack it wherever you'd like Snowball to live, such as your home folder.
+3. In the `snowball` folder, run `install.sh`. That adds Snowball to your applications, and starts it whenever you log in. (`install.sh --uninstall` removes both again.)
+4. Open Snowball from your applications.
+
+To update, quit Snowball from its icon in the top bar, unpack the new release over the old one, and open it again. Your files and settings are kept elsewhere.
+
+## Feedback
 
 Found something wrong, or odd? Email [snowball@temporary.nz](mailto:snowball@temporary.nz).
+
+---
+
+Android is a trademark of Google LLC. Linux® is the registered trademark of Linus Torvalds in the U.S. and other countries.