What is the easiest way to reclaim HD space on an ipad2 without having to sync? Ideally I'm looking for an app that would allow me to delete files directly from the iPad (I remember there was one for the Newton that did this quite well, yes I'm old).
I use the free iPhone Explorer to mount my iPod touch in the Finder, and I can find individual files and copy them to the Mac or delete them without using iTunes or syncing. It is supposed to work with iPad as well. Give it a try.
iOS, which is the operating system that runs on your iPad (iPhones too), is famous for it's somewhat radical approach of not having much of a "file system" to speak of. Technically it's still there, but users never see it; so it's safe to just forget that detail. All that data that you're used to seeing in the file system is now literally stored inside each respective app. So if you play a game, all your progress and anything you download for that app is entirely located in that app. If you have a text editor/viewer app, then all your notes and documents are also inside that app. Apps can "share" content, but it's really making a copy and if the receiving app happened to keep that content (which they usually will do), it would then be in both apps. If not, it's still in the original app. A common example is when you open a photo editor app and you import a photo from your camera roll/photo album. Same thing.
What this boils down to is that to free up space you have to use the apps themselves to delete the data that's inside them. Alternatively, you can just delete the entire app by holding down on the icon in your home screen for a bit and tapping the little x near it. This will effectively delete all the content, data, preferences etc. along with the app itself all at once. Reinstalling the app from the App Store again is totally free of charge, but it will be back to square 1 as if you were installing it for the 1st time all over again. So don't do this with apps that have content that you don't want to lose.
There are some exceptions when it comes to the default apps. They cannot be deleted as a whole, but you can still delete the content inside manually using each respective app.
Tip - videos are what take up the most space of all. So try not to keep a lot of your recorded or downloaded videos on the device. If you happen to jailbreak your device, there is a great iPad/iPhone app called AppInfo that can sort all your installed apps by size and it even accounts for the content currently inside them unlike iTunes which won't account for content inside app.
PS - as far as the 'without having to sync' part, iOS version 5, which is coming this fall, will add a ton of functionality to the device itself that used to require syncing with iTunes. So the bore of syncing might very well be 100% avoidable at that point.
Like any other iOS device you can easily reclaim space by deleting an app manually using the 'x' button after holding down an icon.
You mean that you want to release space on iPad, right? If you want to free up space, you can delete some unused apps or videos. Also you can learn other ways how to how to free up space when storage is completely full.