A team as suggested by the name, is a tool to help developers work collaboratively on their apps. Basically it allows you to add team members to your App and give them various rights. You may read a little more about why we created teams on our blog
You may also have a look at our tutorials on How to manage teams :
An App is the web or android application that you are building using our API. It has a username and an appname You may have a look at the difference here :
and learn how to create an app.
The analytics on your dashboard are data on your application and the activities on it e.g how many messages were successfully sent per Telco. Need more info email firstname.lastname@example.org