Greetings from Syncfusion. We have analyzed your query and we would like to inform you that while using the custom fonts in your application, you need to set different syntax for each OS.
For iOS, we have to give the exact name of the file, without the extension. For Android we have to give the filename with the extension as per the below code snippet.
Please use the font.ttf file code on the XAML code as mentioned below.
<On Platform="iOS" Value="Roboto-Regular" />
<On Platform="UWP" Value="/Assets/Roboto-Regular.ttf#Roboto" />
<On Platform="Android" Value="Roboto-Regular.ttf#Roboto" />
We have created a sample in SfAutoComplete as per the code snippet provided. Please have the sample for your reference.
Please let us know if you have any concern about this.
Muneesh Kumar G.