Data Collection Methods

Flow supports two main first-party data collection approaches:

• Tag-Based Data Collection (Traffic Data)

• PII (Personally Identifiable Information) -Based Audience Sharing

1. Tag-Based Data Collection (Traffic Data)

• Flow provides a tracking tag that the publisher places on their website.

• The tag is deployed through:

  • Google Tag Manager (recommended)

  • Directly in HTML or JavaScript

• Flow captures website traffic data and segments users based on their page visits, interests, and behaviour.

• These audience segments are then made available for ad targeting.

Platform	Audience Segmentation Method
Meta	A pixel is created, and audiences are segmented within the pixel. These segments can be shared individually.
Google Ads	A full tag is created. Since Google Ads does not allow audience segmentation within a single pixel, Flow pre-segments the traffic before sharing.

To streamline segmentation across Meta and Google, Flow recommends assuming that all data entering a pixel is already pre-segmented before sharing.

1. PII-Based Audience Sharing

• The publisher provides hashed customer data (e.g., email, phone number) to Flow.

• This data is uploaded to Meta and Google Ads to create custom audiences for targeted advertising.

• Publishers own the audience but share access with Flow.

To ensure security and compliance, all PII must be hashed using SHA-256 before uploading.

Item	Description	Requirement	Hashing
Email	Customer e-mail address	Required	SHA-256
Phone	Number with country code (e.g. +27xxxxxxxxx)	Recommended	SHA-256
First name	Customer's first name	Recommended	SHA-256
Last name	Customer's last name	Recommended	SHA-256
City	City of residence	Optional	SHA-256
State/Province	State/Province	Optional	SHA-256
Country	Country (ISO 3166-1 alpha-2 format, e.g., US, ZA)	Required	Plain text
ZIP code	Postal/ZIP code	Optional	SHA-256
Date of birth	YYYYMMDD format (e.g., 19900315)	Optional	SHA-256
Gender	M (Male), F (Female), O (Other)	Optional	SHA-256

• Only the Country column remains in plain text.

• Before hashing, ensure that emails, phone numbers, and names are lowercased and trimmed of extra spaces.

• Never store raw PII after hashing is complete.

Below is an example of before and after data hashing:

-- Before Hashing
email,phone,first_name,last_name,city,state,country,zip,dob,gender
[e-mail],[phone],John,Doe,Cape Town,Western Cape,ZA,8001,19900315,M

-- After Hashing
email,phone,first_name,last_name,city,state,country,zip,dob,gender
2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824,
7b8b965ad4bca0e41ab51de7b31363a1c873db5a27f259d146fdbc716f2fdf37,
3b5d5c3712955042212316173ccf37be800af5e01a82c4de90d75ff5f42b2fa2,
4e07408562bedb8b60ce05c1decfe3ad16b722309245f5caed37e38034f17772,
1c383cd30b7c298ab50293adfecb7b18,3f786850e387550fdab836ed7e6dc881,ZA,
b2e98ad6f6eb8508dd6a14cfa704bad7,69faab6268350295550de7d587bc323d,
e1671797c52e15f763380b45e841ec32