Apps to Sync Contacts

Google Sync was a free service offered by Google to synchronize mail, contacts, and calendar data across multiple devices and platforms. It leveraged various protocols like Exchange ActiveSync, CardDAV, and CalDAV to push updates in real-time, ensuring users had consistent information wherever they accessed it.

Toky is a comprehensive cloud-based phone system designed for businesses, offering voice calls, SMS, call recording, and integrations with various CRM and business tools. It provides teams with a flexible and powerful communication platform for customer support and internal collaboration.

Telzio provides a cloud-based business phone system offering voice, SMS, and fax services. It includes features like Auto-Attendant, Call Queue, Call Recording, and secure VoIP calls, designed for businesses seeking a flexible and scalable communication solution.

AkrutoSync is a powerful and privacy-focused software solution designed to automatically synchronize your Microsoft Outlook data, including contacts, calendars, tasks, and notes, across all your connected devices, such as smartphones and tablets (iOS, Android, Windows Phone), without relying on the cloud.

TypeApp is a sophisticated mobile email client designed for managing multiple email accounts effortlessly. It provides a unified inbox, push notifications, calendar integration, and a range of features to enhance email productivity on the go.

Zaclys ownCloud provider offers a robust, hosted ownCloud solution for secure cloud storage, file synchronization, and collaboration. It emphasizes privacy and control over your data, providing a feature set for individuals and organizations to manage files, calendars, and contacts securely online.

gSyncit is a robust Outlook add-in designed to synchronize your Outlook calendars, contacts, tasks, and notes with various cloud services and applications. It provides two-way synchronization, ensuring your data is consistent across all connected platforms, including Google Calendar, Google Contacts, Toodledo, Todoist, Rescuetime, Evernote, Simplenote, and support for CalDAV and CardDAV.

Soocial was a cloud-based synchronization service designed to keep your contacts consistent and up-to-date across various devices, applications, and platforms, including computers, phones, and web services.

Plaxo is a comprehensive online address book and contact management service designed to keep your contacts organized, synchronized, and up-to-date across various devices and platforms. It offers robust features for merging duplicates, integrating with popular services, and providing a unified view of your network.

GO Contact Sync Mod is a reliable and open-source tool designed to synchronize contacts, calendars, and tasks between Microsoft Outlook and your Google account. It facilitates seamless two-way synchronization, ensuring your information is consistent across both platforms.

GroupMe is a free group messaging app that makes it easy to stay connected with friends, family, and colleagues. With its intuitive interface and cross-platform compatibility, GroupMe simplifies communication for any size group.

fruux is a robust cross-platform synchronization service designed to keep your contacts, calendars, and tasks seamlessly in sync across all your devices and applications. It offers a secure and reliable cloud platform with strong privacy focus, ideal for individuals and teams needing consistent data access and collaboration.

Baïkal is a lightweight and easy-to-use CalDAV and CardDAV server, providing a simple way to sync your calendars and contacts across various devices and applications. Built upon the robust sabre/dav library, it offers a straightforward administrative interface for seamless management of users and data.

SOGo is a powerful open-source groupware server designed for scalability and simplicity. It provides a comprehensive suite of collaborative features including webmail, calendaring, contact management, and task management, with strong support for standard protocols like CalDAV and CardDAV.

FullContact is a comprehensive platform designed to help businesses and individuals manage, enrich, and unify their contact information. It goes beyond a simple address book, providing powerful tools for cleaning data, discovering professional details, and integrating with existing workflows to create a complete view of every contact.

ContactUp is a versatile platform designed to consolidate your online presence. It allows users to create a centralized hub for their professional portfolio, social media links, creative work, and contact information. It simplifies networking and content sharing by providing a single, easy-to-manage link.

Nylas Mail, an extensible open-source email client, offers a unified inbox, robust search, and calendar integration. It supports multiple accounts and provides features like email tracking and undo send, aiming to enhance productivity and email management for users.

WeChat is a comprehensive mobile app offering instant messaging, social networking, payment services, and access to a wide range of mini-programs. It facilitates communication through text, voice, and video, supports group interactions, and integrates various lifestyle services.

Cozy is a personal cloud platform designed to give users control over their digital lives. Store, sync, and share your photos, files, contacts, and calendar in a private and secure environment. It offers a suite of integrated applications to manage your data.

MyPhoneExplorer is a comprehensive desktop application designed for managing Android phones and Sony Ericsson devices from your PC. It offers a wide range of functionalities including contact, calendar, and SMS management, file transfers, backup and restore, and screen mirroring, providing PC-based control over your mobile device.

iCloud is Apple's comprehensive cloud service offering seamless integration across all Apple devices for storage, synchronization, and backup of photos, videos, documents, and app data. It provides a centralized hub for managing personal information, facilitating file sharing, and enhancing security with features like end-to-end encryption.

Nextcloud is an open-source, self-hosted platform for file synchronization, sharing, and collaboration. It provides a private alternative to commercial cloud storage services, offering a comprehensive suite of tools including file management, calendar, contacts, and notes, all under your control.

Postbox is a powerful and customizable email client designed for professionals managing high volumes of email. It offers robust features for organizing, searching, and managing multiple accounts efficiently, enhancing productivity through a clean interface and advanced tools.

Threema is a secure and private messaging application that prioritizes user anonymity and data protection. It offers end-to-end encryption for all messages, calls, and files, requiring no phone number registration to enhance privacy.