You will have fixed set of fields created in Community module by default, most of them can be renamed/edited as per your apps needs.
But sometimes you need totally different set of fields or you want to add one more field then you can create custom fields from this tab/page.
Custom fields will work only if you have custom profile module installed/added into your app, if you don’t have custom profile module it will show message like this.
Once you add custom profile module , you will be able to see page like below. This is confirmation page before you import fields from Community to custom profile module.
Once you click create default fields in Profile module button, it will import all the fields from Community to Profile module. And then you can add/edit fields in Profile module and it will sync with community module. This way you will be able to create fields in Profile module which will be used on signup/search in community module.
After Importing fields you will see some settings to change how search functionality works.
Custom fields allows you to define how fields will behave when matching profile.
For example, you have created age field , you want the system to find exact match, range or like ( similar matching few things).
This way whenever you add new fields for search criteria you can define how should it behave.
This settings is available for only Search Fields Section, other section fields will be used for data capture/display purpose, no search operation will be considered.
You can add upto 10 fields into search/profile match section, other section can have any no. of fields.
When you add new fields in Profile module, you need to click save/sync in this page to show newly added fields here.
Having such functionality gives you power to design any kind of app.