or ES file explorer. You can backup your apps as well as remote into your computer with the program to copy files back and forth. And it is a smaller file than Astro. And it doesn't "expire" like astro where you have to upgrade every few months because it will go bad.
App is called EStrongs File Explorer in the marketplace.
AppMonster is a nice (free) app-backer-upper that I have been using for months. The big limitation though with most of these is that unless you've rooted, you wont be backing up paid, copy protected apps. The upside though is that if you are downloading through the Android Market, your app purchases are being synced to your google account and should be auto-downloaded again for you if you sign into another device (or hard reset the same device) as long as you use the same google account.
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