CircleFund: Group record book

CircleFund is a record book for rotating savings groups, known in Vietnam as hụi, họ, biêu or phường. It only records: no money is held or moved. The organizer keeps the book and sees everything: who takes the pot, who has paid, how much is still missing. Each member sees just their own part in the app: how much they pay and whether it was recorded. No account, phone number or email needed; no ads.

How it works: a group has a set number of shares, and one person can hold more than one. Each round, one share takes the pot, the money collected, and the other shares pay in.

What it does
The organizer can:
• Create a group in a few steps from a template: monthly with bids, weekly with bids, or without bids. You can change the amount per share and the number of shares
• A bid is the amount a member wanting the pot gives up; shares that have not taken the pot pay that much less. Without bids, no share pays less
• Add the members and their share counts, and invite one person or everyone by link or QR code
• Open a round, postpone it if needed, enter who takes the pot and the bid so each member sees what they pay
• Record each amount received; to fix a mistake, cancel the entry before the round ends: the old entry stays and a cancellation entry is added
• Close the round, post announcements, see every entry and recent activity, or stop sharing with one person
Members can:
• Paste the invitation link into the app, or scan its QR code
• See their own shares, what they pay this round and their own lines
• Report that they paid, confirm they were handed the money once the book shows it, and ask a question about a line
Also:
• Large text and a language picker
• In Vietnamese only: amounts written out in words under money fields, and the local word (Hụi, Họ, Biêu or Phường)
• Practice mode to try the organizer side, kept on the device

Who it is for
Anyone in rotating savings groups, or running one, wanting a clear record instead of paper or scattered messages. CircleFund comes in 13 languages, is for adults 18 and over, and shows amounts in Vietnamese dong (VND).

Sharing and privacy
• The content (names, amounts, notes, announcements, questions) is end-to-end encrypted: the server holds the encrypted copy and cannot read it
• The server still knows which devices belong to which group (by public key), each device's role and status, the size of each entry and when it arrived, how many entries each device wrote, the invitations (term, use count), and when a payment report is sent. Cloudflare, the host, sees the IP address of every request, and a hashed copy is kept when you create a group
• Someone asking to join gets a 4-digit device code. The app advises the organizer to compare it with that person before letting them in. CircleFund does not check anyone's identity
• Notifications are off by default. If you turn them on, you get three kinds only (a request to join, being let in, a payment report), with no names or amounts. The server then also keeps your notification token and the app language
• The keys that open your book are saved with Google Block Store when the device supports it; you can also save a password-protected backup file and restore it on a new phone
• "Delete my data" in Settings (needs a connection) deletes the groups you organize from the server, for everyone in them, removes you from the groups you joined, and deletes your notification token and this phone's data
• Left in place: what you wrote in groups you do not organize (kept on the server as encrypted data), content on other members' phones, and a backup file you saved, which still holds your keys

What CircleFund does not do
• It holds and moves no money, and does not pick who takes it
• It does not check the people taking part, and the book has no legal value
• If the organizer loses the phone without a backup, no new entries can be added; members keep the lines already loaded

To begin, tap "Try a practice group", create your own, or paste an invitation link.