A caregiving record is an unusual object. It is written by several people, about a person who is not one of them, and it contains the most private facts a family holds: diagnoses, medications, money, and the honest state of somebody's memory.
The subject of that record did not sign up for anything. She agreed to no terms, chose no service, and in many cases could not meaningfully consent to either. Every design decision in Kin follows from taking that seriously.
The fix is not another app feature
Families do not fail at this for want of features. They fail because the two tools they already have are the wrong shape. A group chat is a river: it has no state, nothing can be looked up, and by message 1,200 the dose change is unfindable. A shared document forks — nineteen tabs and four versions of the same medication list, none of them dated, none of them agreed.
What is missing is not notifications or a nicer interface. It is a record: one ordered, dated, attributed set of facts that everyone reads from, rather than several people's separate impressions of a conversation.
Where that record should not live
The obvious way to build this is a cloud database with every family's record in it. It is easier to build, easier to sync, and easier to add features to. It also creates a single store of the medication lists and cognitive decline of a very large number of ageing people, held by a company, in a country, subject to whatever that company later becomes.
That store is a liability from the first day. It can be breached, subpoenaed, acquired, or quietly repriced — and the argument for selling access to it gets stronger every year it grows. The only durable protection against a database being misused is not to have built it.
Kin is the private version
The record lives on the caregiver's own phone. It syncs only to your own private iCloud, and there is no database of ours holding your parent's medicines — which means there is nothing at our end to sell, to leak, or to be asked for.
It also means we are honest about the limits. Kin is a coordination record kept by a caregiver for their own use — what you would have written on the fridge, in a form that holds up months later. It is not a medical chart, not a pharmacy system, and not a HIPAA-covered service, and it will not file or forward anything to a doctor, an insurer or a facility on your behalf. If a clinician wants the history, you export it and hand it over yourself.
And it is funded the plain way: free to try for 7 days, then $0.99 a month or $7.99 a year, with no advertising and no data sale. That last clause is not incidental to the privacy argument; it is the privacy argument. An app has to be paid for by something, and here it is the subscription — never the record itself.