Welcome to Vodafone Community
what is the purpose of the small white or light blue light on top left side next to the front flash?
It is only on occasionally and then seems to pulse?
Checked manual and the net, no luck?
I agree, it sounds like the Notification light. If you go into Settings, it should be possible to control what you get notifications from. Exactly where depends on the device, but if there's a Personalise option, it may be there. In some cases, it's also possible to choose the colour.
On my HTC, it also doubles as the charge indicator - red for charging, green for complete.