How to identify your mobile phone's model?

For Apple iPhone 

Go to Settings > General > About. To the right of model number, you'll find the part number. To find the model number, tap the part number.

For Android Phone

The easiest way to positively identify your phone is to check the Settings page. Drag down from the top of the screen to show your notifications, then click on the gear icon in the upper left corner to open Settings. Then, scroll down to the bottom of your phone and click About Device. (If you don’t see this option, you might have to go to the System tab first.) Your phone’s model name and number will be shown.