I have recently started using Dronedesk for my flight planning and wish I'd done it YEARS AGO. It's superb, user friendly and cuts down faffing about with drone shoot planning by a mile. I used to have a bookmarked folder full of websites I woudl have to go through one by one to plan jobs. Dronedesk automates them all.
It's fast, efficient, comprehensive, educational and user-friendly.
As an unexpected bonus, there's a lead generation tool and a list of relevant public contract tenders, so it's a new business tool as well as a flight planning one.
It really is great.