The selection filters option is used to filter the list of records contained in the linked app. This is ideal for handling large data sets. Setting this up is similar to setting up conditional logic on fields within an app. 

To access the setup options, go to your Apps from the Side Navigation and click the desired App to go to the App Designer page. There, either create or select the 'Record Link' Field. On the modal, click the 'Selection Filters' button.

When setting up selection filters, first select a field in the linked app that you wish to use as the filter (left column).

Then you will select the operator. Depending on the chosen field, different options are available:

This facilitates the creation of very specific rules to offer the user only those choices that fit the criteria.

After that, you have two options. If you don't use the "is empty" or "is not empty" operator, you can use a value that's in the field within the record with the record link field, or you can define a value in the final column.

Finally, if you don't use the 'is empty' or 'is not empty' operator, you can either select a field in the app with the record link field to be the filtered value or define the value to use as the filter in a text capture field.

You can add multiple conditions following the steps described above.