RailUp only uses what it needs to work: no analytics, no advertising, no tracking — so there is no cookie banner.
Cookies
Sign-in session (set only when you have an account, httpOnly, expires when you sign out): keeps you signed in.
rail_locale (about 13 months): remembers your language.
Both are strictly necessary for the service you asked for, so they need no consent (LSSI art. 22.2).
Storage on your device
The app keeps your settings (hide balance, digital assets) and your shared-expense groups in your browser's storage, and caches its own files so it opens quickly and can show an offline screen. Deleting your account clears them; so does clearing your browser's site data.
When you join a table's bill, your phone keeps a random key that proves which guest you are on that bill, so you stay joined if you reload the page.
What we don't use
No analytics cookies, no advertising or social-media trackers, no fingerprinting. If that ever changes, we'll ask first.