The best use case for these awesome cables is actually for charging accessories that mostly stays on your desk: wireless keyboards, wireless mice, tablets, battery packs, USB LED torches, Bluetooth headphones, game controllers, and soooo much more. Once you start charging them with Plugies, you will start wanting to add it to every USB accessory you own. It saves you from the annoyance of plugging the micro USB port the right way a thousand times every month.
Many folks would buy only one cable and use it for their phones, but imo that's not the best use case as it does not support quick charge, and it gets annoying if you want to borrow a charger while out. They come loose easily when you move around.
I miss these cables. As anyone who has bought magnetic usb cables would know, there are no standards and therefore these plugs come in numerous confusing "versions", shapes and sizes.
The very original design was packaged and sold by HKW in Japan years ago, and these Plugies had been consistent and use the same design with a centered row of 5 pins, so they are all backwards compatible.
So buy a handful of these and equip it on all your home accessories, before they are all sold out forever.