[musa-kal]

Guide updates for the settle up release.

• settle up: either direction, between others, past dates, the payment page, pay with an app, Remind, settle everything, settling with a friend, archived groups
• account: payment methods and who can see them
• friends: totals across groups and settling with a friend
• notifications: payment changes and reminders
• roles: who can record and change payments
• small fixes in currencies, balances and privacy

The old settle screenshot is gone; it showed the previous picker.