How do I open multiple charts?

Tabs - You can have multiple tabs open with different charts by pressing on the + icon at the bottom left of your chart as can be seen in the image below and the charts can be removed by pressing on the bin icon.

Multiple Charts at once -Opening multiple charts all at once can also be done by pressing on the 3 lines at the top right corner of your chart and then pressing on New window, this will prompt a chart to pop out in a new window.