Mark,

Here's a quick Xamarin.iOS sample I made up to demonstrate changing the text messages. If you need something more detailed, you'll want to use the documentation Darrell provided to derive your own pull down cell.

Hello Mark

You are looking for properties off the IGPullDownCell class.  (http://help.infragistics.com/iOS/2016.1/igapi/Classes/IGGridViewPullDownCell.html)  Most specifically the pullDownText, ReleaseText, and updatingText.

In our help documentation is a walkthrough demonstrating how to modify this text (http://help.infragistics.com/iOS/2016.1/?page=IGGridView_Enabling_Configuring_Pull_Down_Reload.html) .  On this page is  a link for "Customize Pull Down Cell"

Hope this helps.