How to pause and resume download from remote server to SDCard

I was wondering, is it possible to pause download, exit the app and resume download of a file from remote Server to the phone's SDCard upon re-start of the app.

And follow up question: I have a code that downloads through 开发者_运维技巧HTTP. Can I also do it via FTP? Which is better?

Any suggestions will be highly appreciated.

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This question has some info on resuming downloads in Android. Basically you need to check for a partially completed download, and if it exists, check the file size. You can then pass this value in the header of your request, to resume the download from that location.