User ID

You can identify a user in the VWO SDK by using a string that identifies that user.
User ID can be set in the VWO Launch config.

User ID helps VWO identify a user across multiple devices, and allows it to serve the same variation to a user thus keeping the experience consistent.

For example, you may run a campaign on both iPhone and iPad. If a user installs both the iPhone app and iPad app, setting the user ID will allow VWO to serve the same variation for a campaign.

VWOConfig *config = [VWOConfig new];
config.userID = @"<uuid-for-the-user>";

[VWO launchForAPIKey:@"<your-api-key>" config:config completion:^{
    //completion code
} failure:^(NSString * _Nonnull error) {
    //error code
}];

let config = VWOConfig()
config.userID = "<uuid-for-the-user>"

VWO.launch(apiKey: "<your-api-key>", config: config, completion: {
    //Completion code
}) { (errorString) in
    //Error code
}

Note that altering the traffic allocation among variations or total campaign traffic can break this. Also, changing targeting while the campaign is running is also not advisable.

📘

Please note

User ID is used as hash and is not stored anywhere on the device or server.