Jerboa shows promise, but it feels like it’s not quite there yet. There are still some important features missing (e.g. selecting the language for a post) and frequent bugs.
As a better alternative, you can also use a browser that allows you to install Progressive Web Apps on the phone (e.g. Firefox or Vivaldi).
Just open your Lemmy instance in the browser, press the menu button and then “install”. This will then create a shortcut on your desktop which lets you launch the web UI of your Lemmy instance as if it was a native app on your phone.
For me this works much better than Jerboa.
I am using Vivaldi, and this allows me to e.g. control how I want to open a link. If I just click it, it opens in the same PWA window as Lemmy (useful if you follow internal links on Lemmy). If you long-press it, there is an option to “Open with Vivaldi”, which then opens the link in the regular browser activity, which is useful for external links.
I guess this is the actually best way to use Lemmy on a phone. Either Chromium or Firefox based browsers work.