This is the (Samsung UK) Warranty Policy I can see under Mobile Devices (trying to find more detailed Warranty Terms):
Warranty Policy
Warranty periods and warranty services are intended as a guide only and variations may occur. The warranty period applies from the date of purchase by the first customer and is transferable only between end-users. The warranty covers manufacturing defects only. Please note that this does not include consumables items such as batteries, bulbs, and ink cartridges unless listed above under 'general information'. The liability of Samsung Electronics (or its appointed maintenance agent) is limited to the cost of repair and/or replacement of the product under warranty. The warranty is invalidated if the defect is caused (howsoever) by misuse, neglect, and tampering or incorrect adjustment. It is invalidated if unauthorized persons carry out any alterations and/or repairs. Also, the warranty is invalidated in the following cases:
For the repair of a domestic product used in a commercial environment
For repair due to incorrect installation in your home
For repair to any product where the serial number has been removed
damage that is attached to or used in connection with the product. Samsung Electronics (UK) Ltd support a product purchased in Europe if it has an EU Bloc Warranty. This warranty is present where the top of the product warranty card clearly states 'European Bloc'. If the product is purchased in another part of the globe then Samsung may attempt a repair. Samsung Electronics (UK) Ltd cannot guarantee the outcome.
To obtain technical assistance or to book a service/repair to your product under warranty, please contact our customer care centre. To assist our customer service team, please have your model number, serial number and date of purchase ready when calling.
Maybe using a non-Samsung accessory comes under "incorrect installation"? It's also becoming the norm (at least in the city centre pubs I visit) where you can use a charging hub for your phone, you put