After surveying more than 1,100 Wirecutter readers and using six iPads to test 19 top models, we can safely say that Anker’s PowerPort 4 is the best USB wall charger for most people. It costs a little more than Apple’s single-port 12W USB Power Adapter, but the Anker model can push out more than three times as much power and charge four devices at once. In fact, it can simultaneously charge three full-size iPads at full speed while also charging a smartphone. Surveyed readers said they preferred chargers that plug directly into an outlet, and this is the most powerful one we tested to do so. Additionally, Anker’s charger allows connected devices to draw the advertised amount of power; some of the competition doesn’t.