The summary page is present only in the Android/iOS app. It contains 2 tabs.
The left tabs shows the money flow in each displayed period.
You can change the periods shown using the magnifying glass button on the top menu.
A summary view shows the money flow in the period, not the money you have.
Your funds are kept in the accounts. Check the "Accounts" page if you want to know your total savings.
The right tab displays the amount spent in each category.
You can filter the results by account, date and category type.