I use PocketFMS (
www.pocketfms.com) on my HP5450. Very good and with a GPS attached you get a moving map. It's donationware so you can pay if you like it.
The program does planning, weight and balance, and the moving map with various zoom levels. you need to download the maps and elevation data for your region from the net to get the best out of it.
I have no connection with this product..Honest