In Atlas, you can zoom in on the map by using the + icon on the map or by double clicking on the map. There is a third way, if your device has a keyboard: You can zoom into an area that you ‘draw’ on the map, using the Shift Key. You can even select an object in the same step. This is how you do it:
Tip 1: Zoom into a selected area on the map
Action: Hold Shift Key while dragging a box on the map
Result: zoomed in on the selected area
Tip 2: Zoom in and Select objects to a selected area on the map
Action: Go into Select mode, then Hold Shift Key while dragging a box on the map
Result: Objects selected and zoomed in on the selected area
This video demonstrates both: