Gooloo via Amazon offers Prime members its Gooloo 3-Coil Qi Wireless Charging Pad for $23.99. Coupon code "C64VLI25" drops it to $17.99. Plus, Prime members bag free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $6.44.) That's $46 off list and the lowest total price we could find. It's compatible with all Qi-enabled devices.