Google Calendar is a cloud based calendar from Google.

Memotoo sync all your contacts from Gmail, Facebook, phone, Thunderbird, Outlook, etc in a single address book.

Calvetica is a fast calendar for iPhone and iPad.

Picatic is an event registration platform.

uebermaps allows you to discover & share your favourite spots. Create maps with friends, family for free.

Badoo is a dating-focused social network.

Wooclap is a collaborative platform for your conferences and your training sessions.