Custom Reports are created from saved Filters. The possibilities are nearly limitless, so we'll use a specific example here for demonstration purposes. Maybe you want to start rolling your coverages whenever an opponent demonstrates a strong tendency toward the field (wide) side in passing situations.
Select a team from the Dashboard.
Tap or click the "Tendencies" tab at the bottom of the screen.
Select the phase you want to review.
Choose "List" to load a table of plays.
In the "Down" column, tap or click any table cell with "3rd" to apply the "3rd Down" filter.
In the "Play Type" column, tap or click "Pass" to show only Passing plays.
Set the "Yards to Go" slider to "6-13+ Yards" (or whatever range you consider "Long" on 3rd Down) to limit the plays to that range.
The resulting List shows only the 3rd Down Pass plays with 6+ Yards to Go. Tap the "Save" button in the upper right corner.
You can enter a custom name or use the default "3rd Down • 6-13+ Yards to Go • Pass".