If I delete all my photos on my iPhone can I get them back?

If I save my photos to my computer but delete them off my iPhone will I be able to recover them or put them back onto my iPhone's camera roll?

Yes if they are on your computer.

If you have save them on your computer, you can add them back to your phone.
This may help:
http://support.apple.com/.../kb/PH1693

But what if you have not saved them to your computer? Can I recover deleted photos from iPhone?
Yes, you can. Though iPhone uses quite a different storage mechanism, still you can recover deleted or lost data (such as text messages, contacts, photos etc) with a third party specific iPhone data recovery software called Tenorshare iTunes Data Recovery. I used it to recover deleted photos and contacts from iPhone 4s and it worked. You can download it from https://t.co/Y8pHj3sU
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