fruux - Free service that takes care of your contacts, calendars and more so you don't have to.

AirDroid - Access Android phone/tablet from computer remotely and securely. Manage SMS, files, photos and videos, WhatsApp, Line, WeChat and more on computer.

FullContact - Put the power of full contact information into your web or mobile apps.

Pushbullet - Pushbullet - Your devices working better together

Google Contacts - Google Contacts is Google's contact management tool that is available in its free email service Gmail, as a standalone service, and as a part of Google's business-oriented suite of web apps Google Apps.

MyPhoneExplorer - WHAT IS MY PHONE EXPLORER? Imagine if your PC could be used to keep track of your mobile phone? How would you utilize a PC client that connects to your phone? Read more about MyPhoneExplorer.