Your iPhone 6S can already support wireless charging
Qi-compatible charging case for iPhone 6/6s/7, gold - INBAY
Wireless Charging Receiver Charger for iPhone 7 Plus 7 6S 6 Plus 5S 5 SE 5C UK | eBay
Wireless Charging Case for the iPhone 6 Plus / 6S Plus case - Aircharge
Best Buy: STACKED External Battery Case with Wireless Charging for Apple® iPhone® 6 Plus and 6s Plus Black 14390VRP
Black-Silver ( for iPhone 6 Plus/ 6S Plus ) : Antye Qi Wireless Charger Pack for iPhone 6
Amazon.com: QI OCEANLOVE Wireless Charger Charging Receiver Case for iPhone 7plus 6Splus 6plus (NO Battery) Built-in and Port Lightning Cable Data Sync Shockproof Protective Black : Cell Phones & Accessories
Wireless Power Bank - IPhone 6/6s Plus - Up' Wireless Charging - Store Exelium - UPM7U02 + UPMAI6SP
Mophie introduces wirelessly charging battery case for Apple's iPhone 6s & 6s Plus | AppleInsider
Add Wireless Charging To iPhone 6s Or iPhone 6s Plus Right Now, Here's How | Redmond Pie