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.
Memotoo - Memotoo allows you to sync your data (contacts, calendar, tasks, .) with phones (iPhone, Android, Samsung, ..
GlipMe - GlipMe is a cloud based address book to manage personal and business contacts.
PhoneCopy - Transfer your contacts and other data between your phone and an online storage. Keep your data in sync, backed up, and accessible anywhere with PhoneCopy.
FullContact - Put the power of full contact information into your web or mobile apps.
Wammu - Wammu is a mobile phone manager using Gammu as its backend.