Back in the 1980s, and probably continuing into the 1990s, every neat gadget was shoehorned into a credit-card-shaped form factor. Magnifying glass? Credit-card-sized. Vinyl record de-duster? Credit-card-sized. And so on.
The Jumper Card continues this excellent heritage by putting a Lightning charger, a 30-pin dock connector and a microUSB charger into the same credit-card-sized package, ready to be slipped into your pocket. But not your wallet, because, like all “credit-card-sized” gadgets, this one is way too thick.