The only non-key item I would allow on my keychain. With this key-sized charging cable you will never have to borrow one. Or run the risk of damaging your rather delicate iPhone cable by taking it with you all the time.
Although the Nomad ChargeKey looks rigid, its middle part is actually flexible so it can charge from almost any USB port.
As long as the development pace of smartphones and batteries is out of pace, backup solutions such as the Nomad Chargekey are much more than just a luxury.
Nomad charges more than smartphones though. Available in a Micro USB version and a Apple Lightning Connector variant it charges portable gaming consoles and camera’s too.