SMS and text messaging
How Cairn uses text messages, and what happens to your number.
What we send
Cairn sends one type of text message only: a six-digit one-time passcode used to sign you in to your account. We do not send marketing, promotional, or advertising text messages, and we do not send newsletters or trip reminders by SMS.
Consent
You provide your mobile number voluntarily when you choose phone sign-in. Entering your number and requesting a code is your consent to receive that one-time passcode by text. Consent to receive these messages is not a condition of using Cairn; you can create an account with an email address instead, and you can switch to email sign-in at any time.
Message frequency, rates, and help
- Frequency. Messages are sent only when you request a sign-in code. There is no recurring or scheduled messaging.
- Cost. Message and data rates may apply, depending on your mobile plan and carrier. Cairn does not charge you for these messages.
- Opting out. Reply STOP to any message to stop receiving texts from Cairn. You will receive one confirmation message, after which no further texts will be sent. Because our only text is the sign-in code, opting out means you will need to sign in with your email address instead.
- Help. Reply HELP for assistance, or email support@thecairnapp.com.
- Carriers. Mobile carriers are not liable for delayed or undelivered messages.
We do not share your mobile number
No mobile information will be shared with third parties or affiliates for marketing or promotional purposes. We do not sell, rent, or trade your phone number. Your number is never shown to other Cairn users, is not used to help people find you, and is not passed to advertisers or data brokers.
The only third party that receives your number is Twilio, the messaging provider that delivers the text on our behalf, and Supabase, which hosts our authentication system. They process it solely to deliver and verify your sign-in code, under their own terms as our service providers. Neither uses your number for their own marketing.
Twilio's privacy notice: twilio.com/legal/privacy. Supabase's privacy policy: supabase.com/privacy.
Storage and deletion
Your mobile number is stored with your account so we can recognise you at sign-in. Sign-in codes themselves are short-lived and expire within minutes. Delivery logs held by our messaging provider are retained on their standard schedule.
You can remove your number by switching your account to email sign-in, or have it deleted entirely along with your account. See Deleting your account and data.