I am pretty sure that if you update an app on device and sync it with iTunes, iTunes will also put the old app in the trash. I love to update apps on the iPad

I am pretty sure that if you update an app on device and sync it with iTunes, iTunes will also put the old app in the trash. I love to update apps on the iPad - it makes it the easiest to see all changes at a glance. And I don't love how I cannot get rid of the update badge on the App Store app. Now I have to remember how many of these are updates I don't want...