The Model Number of an iDevice can be found here:
Settings -> General -> About -> Model Number
It shows one in ML2I2KN/A
format (detailed), and on some models if you tap on it then another will appear - in A1652
format (general). The detailed number is more useful as it provides information about memory and color too.
- Identify your iPhone model (using general number);
- Identify your iPad model (using general number);
- AMR Certification Approvals (using detailed number, hover mouse over the Model Number).
- The iPhone Wiki table has almost every model;
- simply search for detailed number in Google, you'll get some store page with the model description;
- Everyi has some models searchable by detailed number.