Groups

Each group is a self-contained shared history: its own members, expenses and balances.

Creating a group

Tap + on the Groups tab, name the group, pick its currency.

Sharing the group needs a storage backend — the encrypted log has to live somewhere the other members can reach. Without one, the create screen shows a notice you can tap to set one up on the spot.

You don't have to. A group created with no backend is marked Local only and works fully on your device: expenses, splits, balances, settlements, receipts and export all behave the same. It just isn't synced or backed up, and nobody can join it. Add storage later from the banner on the group's own screen and it starts syncing from then on.

Whoever creates a group is its owner (Owner badge) and provides its storage.

Adding members

Open the group and tap the members icon in the header, then choose:

• Add a known friend — anyone already confirmed in your Friends list is added immediately, no link needed.
• Invite someone new — FEN mints an invite link you can share however you like (message, mail, in person). The link expires after 24 hours; mint a new one if it goes stale.

The link carries the group's encryption key in the part of the URL that never reaches a web server. Treat it as a key: anyone who opens it can join.

The recipient taps it to join. If tapping does nothing — some messengers mangle links — they can copy it and use the paste button on their Friends tab.

The icon is missing on a Local only group: an invite points at the group's storage, and that group has none, so there is nothing for anyone to join. Add storage from the banner on the group's screen and the icon comes back.

Adding an expense

Tap the + button and fill in:

• Amount and currency — any currency, not just the group's.
• Group — pre-filled when you start from inside a group.
• Description — what it was for.
• Date — defaults to today.
• Paid by — defaults to you.
• Category — see Categories.
• Split — how the cost is divided.

Splitting

Three split modes sit behind the small icons above the member list:

Icon	Mode	What it does
=	Equal	Divides evenly between the members you tick.
%	Percentage	You give each member a percentage; they must total 100.
123	Exact amounts	You type each member's share; they must total the expense.

Rounding is handled for you: odd cents from an uneven split are distributed rather than dropped, so shares always add back up to the total.

Receipts

The camera icon on the amount row attaches a receipt, three ways: take a photo, choose one from your gallery, or choose a file — which is how you attach a PDF, the form a hotel or an airline receipt usually arrives in, or a picture that lives in Files rather than Photos. Files are limited to 10 MB, because every member of the group downloads whatever you attach.

Photos are downscaled on your device and stripped of location and camera metadata before being encrypted; a PDF is stored as it is. Tap the icon on a saved expense to view the receipt — pictures and PDFs alike open full-screen in the app.

Sharing a receipt to FEN

You can also start from the receipt. Share a picture or a PDF to FEN from any app — Photos, Files, Mail, your scanner app — and FEN opens a new expense with that file already attached. Nothing else is filled in: you still choose the group, the amount and how it splits.

If you share something FEN cannot store as a receipt (a video, an archive, a text file), it says so and does nothing else.

On iPhone, sharing a photo hands FEN a JPEG copy even when the original is a HEIC, so the receipt is readable on every member's device.

Reading the expense list

Expenses are grouped by month, newest first, under two chips at the top of the list:

• Added — the order they were entered in. This is the default: what has happened in the group lately.
• Spent on — the date on each expense. This is the one that reconstructs a trip, and it puts a receipt you entered a week late back where the money actually went.

Tap the chip you are already on to turn the list around, oldest first. The month headings follow whichever date you are sorting by, so an expense entered in September for a dinner in June sits under SEPTEMBER in one order and JUNE in the other.

Editing and deleting expenses

Tap an expense to open, edit or delete it. Deleting marks the entry deleted in the group's history rather than erasing it — that is what lets every device agree on the outcome.

Who may change an expense is per-group, under ⋮ › Who can edit expenses:

• Everyone — any member can edit or delete any expense.
• Only the person who added it — everyone else can look but not touch.

Balances

The group screen shows what you're owed and what you owe; tap through for the full Balances screen, which lists every debt in the group, including ones you're not part of.

Balances are kept per currency — euros and francs stay separate. FEN never converts money silently; nothing is merged unless you supply exchange rates.

Simplify debts

Simplify debts works out the smallest set of payments that clears everything — five people paying in a circle may come down to two transfers.

It is a suggestion until you tap Record these settlements, which writes every suggested payment at once and leaves the group settled.

Settling up

Each debt row has a Settle button: confirm who paid whom and how much, then Record settlement.

A settlement records a payment that happened in the real world — FEN never moves money. Any member can record one, which matters when the payer isn't the one holding the phone.

Multiple currencies and exchange rates

The rates icon in the group header opens Exchange rates — one rate per currency pair the group actually uses. Any active member can set them, and they are display-only: they change how totals are presented, never what was recorded.

Adding an expense in a foreign currency offers to load the rate for you. Until a rate exists, per-currency balances stay separate.

Categories

Categories (groceries, transport, …) are what make the report useful. ⋮ › Categories edits this group's list; new groups start from your defaults in Settings › Expense Categories. Uncategorized always exists and cannot be removed or renamed.

Report

The chart icon in the header opens Report: spending broken down by category, as a pie chart plus a list.

• Payer filter — a scrollable row of members; tap one to see only what that member paid for.
• Currency handling — by default each currency gets its own block. If the group has complete exchange rates, the toggle in the top right combines everything into a single chart in the group currency.

Exporting expenses

⋮ › Export expenses asks which of two files you want, then hands it to the share sheet.

CSV (text only) is the expense list on its own: one row per expense — date, description, category, who paid, currency, total — then one column per member holding their share as a plain number. Summing a member's column gives exactly what they were charged. It is instant and works offline.

ZIP (including receipts) is that same list plus every receipt in the group, decrypted, in a receipts folder. The CSV inside the archive gains a Receipt column naming the file each row belongs to. This one has to fetch every receipt first, so it is offered only when the group has any, and it tells you how many and roughly how much data that is before it starts.

Either way the file is named fen_<group>_expenses_<date> — so a folder of exports sorts by group and reads by date months later.

A receipt your device cannot get hold of — one that has never synced to it, or one from a closed group whose shared copy is gone and that you have no archive of — does not stop the export. It is left out, marked (missing) in the CSV, and listed in a missing receipts.txt inside the archive.

Managing the group

All of these live in the group header:

• Rename group — tap the pencil beside the name.
• Remove member — ⋮ › Remove member. The group's encryption key is rotated afterwards, so a removed member cannot read anything added after their removal.
• Leave group — ⋮ › Leave group. You stop being an active member; the others find out the next time their devices sync. Your copy freezes at the moment you leave and stays on your device as a record. Settle up first if you can — FEN warns you if you leave with an open balance.
• Close group — ⋮ › Close group, when the trip is over.
• Remove from this device — ⋮ › Remove from this device removes the group from this phone and deletes its archives from your saving folder. Irreversible: see Backup & recovery.

Removal is only offered where nothing can be left behind on anyone's storage: a closed group, a group you have left or been removed from, or one that never had a backend to share through. An open group you are still a member of has Close or Leave instead — that is what makes sure a shared copy is always cleaned up rather than abandoned.

Leaving a group

Leaving is not the same as closing. The group carries on without you, and your copy of it stops there:

• It greys out and reads (Left), like a closed group, but only for you — everyone else still sees an ordinary open group.
• Nothing new arrives in it, including settlements. If somebody records a payment to you next week, your copy will not show it.
• On the next sync after your departure has actually been sent, FEN writes your archive (if you have a save folder) and then disconnects the group from the backend. From then on it is a local record and nothing else.

If you might still be settling up, settle first and leave afterwards.

Closing a group

Closing ends the group: no more expenses, no more syncing. Closed groups are hidden on the Groups tab until you switch the filter to show them.

:::warning Set your save folder before closing A closed group is exported to your local save folder as an archive. If no folder is configured, there is nowhere to write it — and your own archive is the copy that survives losing the backend, its credentials, or the keys on this phone.

The close dialog warns you, and the Groups tab lists closed groups still waiting to be saved. Set the folder and they are written automatically. FEN reads those archives back in too, which is how closed groups survive onto a new phone (Backup & recovery). :::

What happens to the shared copy

Closing does not delete the group's copy on your storage — the others still have to sync to find out the group is closed at all. Instead, every member's device saves its own archive and says so, and once all of them have, the organiser's device removes the shared copy on its next sync. Nobody is asked: by then the evidence that everyone holds their own copy is already in.

Two consequences worth knowing:

• The group stays. It is still on every device, still readable, still in the Groups tab under the closed filter — it just no longer takes up space on the organiser's storage. Receipts come from the saved archive from then on.
• A member with no save folder is counted too. They keep the ledger and lose the receipt images, which is the choice they made by closing without a folder. Set one before the shared copy goes and the next sync picks the pictures up.

The organiser gets a notification when it happens, and the group's own screen says so permanently — that is the answer to "where did my storage go?".

Everyone else's device notices too. The next couple of syncs find the shared folder gone, and the group quietly becomes a local-only archive on their phone as well, with a line on its screen saying so. Nothing is lost: they each said they had their own copy, which is what allowed the removal in the first place.

When somebody never syncs again

That whole sequence waits on every member, and a phone that is lost, broken or simply never opened again will never answer. So if a closed group is still waiting 30 days later, FEN asks the organiser instead — on the group's own screen, and with a notification so you do not have to go looking. It names the people it is still waiting for rather than counting them, because who they are is what tells you whether to go and ask them or to give up on them.

You can remove the shared copy anyway, or put the question off; if you put it off, it comes back a month later. Removing it costs those specific members two things: they will never see that the group was closed, and they can no longer take their own archive — receipt pictures included — out of the shared copy. Everyone who did sync keeps everything, and so do you.

If a straggler turns up in the meantime, the question answers itself: their acknowledgement completes the set, the shared copy goes on the next sync the ordinary silent way, and the prompt disappears without you doing anything.