I'm trying to setup the search widget or location setting to use with collector.

[ChetShuler]

The field is an unique ID and formatted as a double and does not appear in the pull down. So I'm assuming the format is limited to text and integers?

[Anonymous User]

Hi Chet Shuler‌,

You are correct, "In the layer, all string and integer fields that do not have coded domains are searchable."

Reference: Configure feature search—ArcGIS Online Help | Documentation 

Hope this helps,

-Peter