Last updated Sep 4, 2026 · Effective before the first payment link goes out

Privacy

Sidenote is a journal you text. Everything you send to the Sidenote number is your journal, and this page says exactly what happens to it. Short version: we store it privately, a few named providers process it so the product can work, nobody trains models on it, and you can take it or erase it with one text.

What we collect

Messages you send to the Sidenote number: text, photos, videos, voice notes, and the time you sent them.
Things we derive from them so the product works: transcripts of voice notes, a one-line description of each photo (used only to write your entry, never shown to you), your nightly entries, and a safety rating on each message.
Account details: your phone number, the name and city you gave us, the timezone we resolved from that city, and your plan status.
Billing details are held by Stripe. We store only your Stripe customer and subscription IDs.

Who processes your content

No person at Sidenote reads your journal. These providers process it on our behalf, each under its own terms:

MessagingSendblue (iMessage delivery). Receives and delivers your messages and media.Message content passes through; media URLs expire after we copy the file.

AIAnthropic (Claude). Writes replies and entries, answers recall questions, classifies safety and intent, captions photos.Sees message text, transcripts, and photos per request. Not used to train models.

Speech-to-textOpenAI or Deepgram (the selected provider will be named here before launch).Receives audio of voice notes to produce transcripts.

Storage & databaseSupabase (Postgres and private file storage).Holds everything. Files are private; every download is a signed link that expires within 24 hours.

HostingVercel.Runs the service. Logs contain timings and error codes, never content.

PaymentsStripe.Handles cards and subscriptions. We never see card numbers.

What we never do

Train models on your journal, or allow our providers to.
Put message bodies, transcripts, captions, media links, or full phone numbers in logs. Logs hold IDs, kinds, lengths, timings, and error codes.
Notify anyone, including us, with the content of a message, even when the safety layer flags it. The daily ops report shows a count only.
Sell, share, or show your journal to anyone.

How long we keep it

Your journal: until you delete it or your account is purged.
Raw inbound webhook payloads: 30 days, then purged.
After a lapsed subscription: 90 days. At day 80 you get a warning and an export link. Then everything is deleted.

Your controls, by text

export sends a link (valid 24 hours) to a zip: one markdown file per day plus your photos and voice notes.
delete last removes your most recent message and its media.
delete everything, confirmed once, erases every row and file within sixty seconds. Only a record that you asked us not to text you survives, if you had sent STOP.
STOP ends all messages from us until you text START.

Safety

Sidenote is a journal, not a mental health service. Messages are automatically rated for risk so the product can respond with a fixed message pointing to 988 (US) and pause check-ins for a day. That rating is stored with the message and never shared.

Contact

Questions about your data: privacy@sidenote.app ↗. We answer within two business days.