You just show the other person the lock screen and ask him toturnon the camera on his smartphone is the easiest way to shareyourcontacts. Add а contact automatically. No more numbers,forwardingfrom another's smartphones and uncomfortable requests toremind thename. The solution is a QR Card. The application makescontactexchange as quick and convenient as possible. An ordinarybusinesscard can simply be thrown out or lost. Contact in asmartphone is acompletely different matter. It’s not difficult,just three simplesteps: 1. You add the information you want toshare on the businesscard. 2. Select a background from the list orupload your own. 3.Set the business card on the lock screen.Together with the finalimage, its background is saved without a QRcode. You can add it tothe main screen of the smartphone. To addyou to your contacts, youdo not need a separate application. Thecamera can alreadyrecognize QR codes. Optional: A QR code on thelock screenincreases the likelihood of your smartphone returning toyou if itis lost. The finder simply scans the QR code and can, forexample,write you an e-mail or call your work phone.

I am pretty sure that this is the best mobile app.