Due to technical limitations, non-straight gestures are not supported on iOS directly. That is, any non-straight gestures undertaken on iOS would execute as a series of "broken" straight gesture components where the "breaks" would be akin to the lifting of the finger if one were using a physical device.
There is however some limited support on Live & App Live for executing non-straight gestures on iOS devices. When executing the gesture on the virtual device either via your system mouse or trackpad when using Live or App Live, press `Cmd + Shift` (if you are accessing BrowserStack via MacOS) or `Ctrl + Shift` (if you are accessing BrowserStack via Windows). After the gesture finishes you may release the keys & mouse click.
There are one caveat to be noted however:
You would not be able to execute non-straight path gestures in realtime, i.e. the gesture would only start executing on the virtual device after the gesture action on your side finishes and the mouse pointer & keys are released.