Gadgets have made easier to perform our day to day activity, so it is very essential they work properly in order to ensure that Apple has technical support department which works 365 days, 24*7 just to ensure you gadgets work error free .One can resolve their concerns by speaking i.e. by calling the tech support department , through online i.e. email , chat and through genius bar reservation
Online method to resolve their concerns is mostly getting picked up these days as you don’t have to wait on the call to speak to the expert at the other end and if the connection is bad when you dial the next time you have to explain the concern all over again to avoid this Hassel you simply go on the website, choose the Apple product that you have a concern for, it will again ask you to choose what is happing to your product is the problem regarding the battery , system performance , Wi-fi connectivity and so forth , once you will choose the concern then again it will ask you the concern in more details related to it you have to choose from the same then it will ask you to enter the serial number for your product and if you do not know they will help you locate the same ,the online Apple expert will be there to help you or you can also ask for the call back as per your preferred time.
Source: Apple Technical Support