I was in need of a tool that could help me organize my calendar and keep to date links and summaries of each activity, meeting or job I have during the day. Best thing of PlanArty is that it will deliver all this, but much, much more... as it has an invoicing feature, time tracking, quotations, project breakdown... If you need it for personal reasons, this options may not be handy, but if you're an entrepreneur, you will surely get a hold of those.

It has a lot of options and functionalities which can be useful if you're running a business or if you need it for personal reasons. Allows you to organize things much better and gives you a better organization and time management. Customer service is amazing.

I have not found any yet. Google calendar integration is bound to happen, for those interested in integrating both tools. Nicest thing of all, any bugs or problems you could find during the way, are taken care of really quick and with a warm and nice feedback.