I have researched and used several e-logs over the years and found the two biggest players to be LogTen and Logbook Pro. I have used both and personally got tired of getting screwed over and over again by LogTen. Everytime I turn around there is some new freaking update they want me to pay for. Then I upgrade my phone IOS 5 and I have to pay again ***....
Just do some simple math and you see which one is more economical. Also read the reviews on Apple about the new version...
-Logbook Pro PC edition is 69.95 (on sale now for $59.46)
-Cloud Backup - don't need it but looks neat
-iPhone and iPad universal app is free
-Cloud Sync is 19.99 for a year (on sale for 16.99)
-Schedule Importer, don't need it but it is $120 for two years (on sale for $102 or $4.25/month) and works so much better than log10's which doesn't even work right
Logbook Pro total cost plus apps is $76.45.
log10 desktop - $149.99
log10 iPhone - $49.99
log10 iPad - $79.99
Total for all three to use: $279.97
On sale at 50% off which is $140 and you get to buy it all again with v7 or iOS 6 or whenever they pull the plug on us again. You can spend $1000's paying for all the updates on LogTen. Don't try and buy a binder from them either. I looked and was redirected by them to Logbook Pro.