I've created a custom search in agol, using a composite geocoder. It mainly searches for IDs for various assets. It works great in our flex viewer web map and the arcgis online web map. However, it only partially works in the agol for ios app. I can search, as long as a user is logged into agol. The majority of our users do not have accounts, and this isn't really an option for them. As soon as I log in, the search works fine. It also appears to work for a short while after logging out. This is a public map, but behind our firewall that our iPad users are able to access.