VK (VKontakte) is the largest European online social media and social networking service. It is available in several languages and is especially popular among Russian-speaking users. Developed by Mail.Ru, Pavel Durov
License: Free
VK is a centralized social networking platform with a focus on multimedia sharing and large communities, particularly popular in Russian-speaking regions. In contrast, Friendica is an open-source, decentralized platform emphasizing user privacy, customization, and community-driven features.