On this video Photoshop expert Jesús Ramirez (from the Photoshop training channel) demonstrates how to create an artificial glass reflection effect using Adobe Photoshop.
Ramirez uses 3 different layers – one of a girl looking at her phone and one of a window and on of a busy city. The idea of this tutorial is to blend them together realistically. The main play here is to use blend modes in a smart way. Adding a green tint can also help (shooting through a window has this effect).
We have looked at reflections several times in the past, Aaron Nace did a video on adding “reflections to sunglasses” a while back and another video called “How to Create a Reflection in Photoshop“. If you are more into shooting reflections and not post processing them – check out Ian Plant’s tips on shooting reflections near water.