Now there are many kinds of wireless charger in market, so when you choose one charger, What features should you pay attention to? Start with these tips:

Grip: A rubber ring embedded in the pad can help keep your phone from slipping around. Without it, one slight bump might knock the two coils out of alignment, disrupting charging.

Coils: All it takes is a single charging coil to power your phone, but you'll see some chargers touting 2-3 coils. What's the advantage? Surprisingly, it has nothing to do with speed: a multi-coil charger just gives you more room on the pad, meaning you don't have to be quite so precise when you lay your phone down. And when it comes to a charging stand, it's preferable to have extra coils because different phones are different heights, and you want to ensure it connects properly. So a small, one-coil circular pad is fine, but if you're choosing a larger charging mat or a charging stand, opt for two or three coils. 

Smart LEDs: Not all charging pads are nightstand-friendly: Some employ very bright LEDs that could prove distracting to light sleepers. Find one when charging begins with soft light

Wall adapter: As noted below in "How does the charger get power?", not all pads and stands come with wall plugs. You may not need one, but check to see if it's included.

Speed: if you want to experience fast wireless charging, make sure that your phone and wireless charger support fast charging simultaneously, also 9v output or above adapter and fast charging cable are necessary.