iPhone: It's a good idea to share a digital contact card after exchanging business cards. Shoot makes customisable, rich digital cards that you can email to anyone so they can quickly add you to their address book.
The app is completely free and does not require the other person to have it installed. You can make multiple contact cards, each with different information. Just add your details (name, photo, company, website, phone number, email, social networks and more) and save it. When you want to share this contact card with anyone, Shoot will send all this information in a rich email, complete with a VCF file so that the recipient can add you to their phone book in a click.