KMHphotovideo - Here is a very useful lens simulator from Nikon. Works same for other brands. If you are planning on getting into photography and buy lenses, start here. Try it for
Camera Lens Simulator - Apps on Google Play
Use Nikon's Lens Simulator to Pick Your Next Lens (Non-Nikon Shooters Too!)
OpticExplorer is a new lens simulator/lens database website - Photo Rumors
What is angle of view in photography? – frederikboving