The concept of portable battery packs that stack up one on top of the other for recharging isn't new. But Otterbox's new OtterSpot system appears to be the first that brings a wireless element to the mix.
Priced at $130 for a base unit and one charge pad -- no, it's not cheap -- you can use the system at home or on the go to wirelessly charge any Qi wireless-enabled device, including iPhones, as well as Samsung and Google Android phones. International prices aren't available, but $130 converts to roughly £110 or AU$200. Additional pads are available for $70 and you can charge up to three pads at the same time (stacked) using the 36W USB-C power adapter. Otterbox is also selling a Wireless Charging Stand for $60.
Although the 5,000-mAh capacity wireless charging pads are a little bigger than your standard portable power bank, they're fairly lightweight and slim and will fit in some pockets just fine. Just don't expect to get them into the front pocket of a pair of tight jeans. They charge devices at up to 10-watt speeds. However, with iPhones, the top charging speed is 7.5 watts.
There's also an option for wired charging from the portable puck using a USB-C cable. For iPhones, you'd need a USB-C to Lightning cable, which costs $15 to $20.
After using OtterSpot for a couple days, I think it's a pretty nifty charging system. That said, I do think Otterbox has to get the base system down to $100, with additional pucks costing $50.