Android

1. On Android device select “Apps”.
   
   
2. Locate “Settings” in the apps menu. This often looks like a gear icon.
   
   
3. Locate and select “About Phone” or “About Tablet” or “About Device” (name is different for all devices). 
   
   
4. Look for “Model Number” or “Model.” Examples of Model Numbers are SCH-i535, etc. (can be anything with letter and number format). The same device (e.g. Samsung Galaxy SIII) can have several different model numbers.

Apple.

1) Tap on the settings (It looks like a cog Icon)

2) Tap on "General".

3) Tap on  "About".

4) You will find both Model number and Software version.