Linka Smart Bike Lock
Instead of locking your bike to a post, tree, or bench, park it wherever you want and let the Linka Smart Bike Lock keep it safe. This frame-mounted lock works wirelessly with your phone to automatically unlock when you approach, and lets you immobilize your bike via a 9mm hardened square steel ring with a single push of a button. It has a built-in 100 dB siren that goes off if someone tries to carry your bike away, tamper alerts it delivers to your phone (within a 400 foot range), and a 4-digit pass code feature you can use to unlock the bike should you leave your phone behind.