todoyu is described as 'extendable, web-based, open source project and task management system. It is geared to the needs of SMEs, tailored to project-related work and suitable for agencies, consultants, architects or lawyers' and is an app in the Office & Productivity category. There are more than 50 alternatives to todoyu for a variety of platforms, including Online / Web-based, Windows, Mac, Android and iPhone. The best alternative is Google Calendar, which is free. Other great apps like todoyu are Redmine (Free, Open Source), Basecamp (Freemium), Wrike (Freemium) and GanttProject (Free, Open Source).