I suspect this is a bug in the Salesforce1 iOS app and that the image formula fields are not supposed to display in this layout at all. This is based on:
- the other devices not showing the link at all, and
- the value being incorrectly HTML encoded in the iOS version, and
- any other selected fields on the layout not displaying. In my example below the Company and Phone fields don't appear on any device. Perhaps only the Name field is supposed to appear.
I did a test and my images appeared in the Salesforce1 search layout.
- Created a test formula field on Leads with the following formula:
- Added the field to the Selected Fields of the Leads Search Results layout. I had to include it in the first four fields as
...Salesforce1 search results show only the first four fields from an object’s Search Results layout Source
- Tried searching for John via /one/one.app in chrome. The image appeared (although cropped).
- Tried the same thing from my phones browser. It appeared, but was also cropped as well
So it would appear at the most basic level the Salesforce1 Search Results page will display images from formula fields.
The issue might be the specific image link that the formula is creating. Possibly in combination with how Salesforce1 is being viewed (I.e. native iOS or Android app). Historically I've seen browsers include the intended image URL as a placeholder when the intended image couldn't be loaded.
What does the HTML source look like for the problem page? In particular, is Salesforce rendering image tags?
As you have noted, when using a browser directly only the Name field will appear on recent items regardless of the Tab Search Layout.
Here is my Lead Tab Search Layout.
As the same layout appears in the iOS Salesforce 1 app.