Account & preferences
Personal preferences, not shared with anyone else signed in to the same install.
Language, font size, and decimal accuracy
A language selector (English or Suomi), independent UI/table font-size preferences, and a default decimal-accuracy setting for numeric entities - the starting point every Dashboard and History entity uses unless its own card editor overrides it.
Changes here are buffered until you click Save - a stray click on a select never silently resizes the whole app.
Sign-in landing page
Choose which page opens right after you sign in, and whenever the app is opened at the home page: Last page visited (the default - keeps the current behaviour) or any visible dashboard. Refreshing while on any other page still leaves you there; this only affects a fresh sign-in and the home page itself. A companion-app device can override this per device - see Companion App.
Contact details
Address and phone number can be added alongside your username and email - not used by Athena itself today, just stored on the account for anything future that might need them (a household contact list, for instance).
Theme
The light/dark toggle itself lives in the sidebar's top brand row, not on this page - see Interface overview.