Reply lets you add custom fields to your contacts. In these fields, you can store additional information about your contacts. Once added, custom fields can be used to filter contacts, allowing you to quickly find those who match specific values.
To apply a filter using a custom field follow these steps:
Open the People page and click Create new filter.
Enter a Filter name (optional). Giving it a name isn’t required, but if you save the filter, it will be easier to find and reuse later.
In the Property field, select the custom field.
Select the IS condition and enter the value. For example, if you create Language custom field, this will filter only the contacts who have that language saved in your custom field, for instance, Spanish. Then click Apply or Save if you want to use this filter again later.
Check the filtered contacts.
Save the filtered results to a separate list or move them to your sequence.