Apart from the design difference - the biggest difference is AirPods are wireless while EarPods are not wireless. The AirPods comes with lot more openings compared to EarPods.
It is very very easy thanks to seamless integration, which Apple has done. All you have to do is to bring your AirPods case near to your iPhone and open the AirPods case. The moment you open the AirPods case, your iPhone will detect it and will give you prompt to connect like the side image. Tap the connect button and you are done. Your AirPods are connected with your iPhone and they are ready to use.
The AirPods will begin charging as soon as they are in the charging case. It does not make any difference, whether the case lid is open or close.
Yes, you can use Airpods with iPhone 7.
If you do not want to use your AirPods with your iPhone, you can disconnect them easily. Follow below steps to disconnect AirPods with the iPhone.
Step 1: Go to Settings
Step 2: Tap "Bluetooth"
Step 3: Tap "information button" besides your AirPods
Step 4: Tap "Forget this device"
Look past their offbeat design and you'll find that Apple AirPods' compact size and high convenience factor are a winning combination.