IMEI what is it and how to find it ?

The International Mobile Equipment Identity (IMEI) is a number, unique used to identify all GSM devices. It has 15 digits. It was usually printed inside the phone on the sticker while you removed battery from phone.

Now while all new smartphones are not possible to open you can check IMEI while typing *#06# like phone number.

How to find the IMEI number in Android devices
method 1. Dial *#06# like a phone number. IMEI number will appear on the screen.
method 2. Go to settings - about the device.
method 3. Older models have the IMEI number printed on the sticker under the battery.
method 4. IMEI number can be found on the sticker of the original box.

How to find the IMEI number in iPhone, Apple devices
method 1. Dial *#06# like a phone number
method 2. Click on settings, general and about. IMEI will be listed with other information about your phone or tablet.
method 3. Connect your iPhone to your PC or Mac with an USB cable. Start iTunes on PC and Finder on Mac.
Click on your device on the panel on the left. Choose General when you have Finder and Summary for iTunes.
IMEI will be listed next to other information about your device.
method 4. Check the sticker on the original box.
method 5. Turn off your iPhone and remove the SIM card tray. The IMEI number is printed either on the top or the side of the SIM card tray.