In a recent article I saw a mention of a "smart" product called Phrame. It looks like a SKSK incompatible security nightmare to me. Phrame is a smart license plate frame that serves as a “safe box” for your car key. It is equipped with sensors and a security system that you can easily install on your car around your existing car’s license plate frame and then connect to your smartphone. From there, Phrame can communicate with your smartphone, enabling the ability to share access to your car via storing your car key inside Phrame’s compartment. This way, Phrame gives you full-control over providing access to your car to whomever you wish via the Phrame app. Moreover, the app provides real-time information directly to your smartphone such as your car’s location, outside temperature and any unusual activity related to your car. The original article said you could give others access to the "hidden" key. I doubt it is compatible with full SKS. Phrame Help: Frequently Asked Questions