Blender - low poly - Unity

Hi, This might be too broad a question (Hopefully it is okay to ask) but I need some advice on creating models in Blender with the intention of exporting them to Unity for use in mobile games. I know that the models need to be low poly but this confuses me because when I search “low poly” on google images I get a very distinct look but when I download games on the app store a lot of them don’t have this look. Is there any guidelines for using Blender for exporting to Unity for mobile games (or any touch device)? Any advice would be great, thanks.