As far as I am aware, it's a File Manager application

 

It's actually incredibly useful worth downloading for when you do need it.

 

From what I can gather, if you want to access your SD card then you do need it, or at least something similar.

 

It's always handy to have a file manager on your phone. Especially if you have a lot of files (photos/musics/doc) saved on your SD card. Also, Astro is more than just a file manager

These are the things you can do with Astro:
- Manage Files, Applications & Tasks
- Read zip, tgz files
- Send attachments
- Task killer
- SD card usage
- Backup & restore applications
- Search text and files
- Image and file viewers
- SFTP, SMB, Bluetooth networking

 

I use Astro or EStrong file managers (either is great) - Estrong's upload / download via wifi to my home network is a godsend. Not sure if Astro has it too ?

 

astro also allows you to install apps that you may heve stored on your sd card as .apk files

its very easy to use and worth having on the phone.

its also free which is nice.

 

Nope it doesn't, it uses bluetooth to transfer files with your PC...I think that's one thing that makes EStrong superior to Astro.