If you setup iCloud and turned Photo Stream on, you can view them on other devices that have Photo Stream enabled.
See this Apple doc for more info -> iCloud: Photo Stream FAQ
When you enable My Photo Stream on your devices, all new photos you take or import to those devices will be automatically added to your photo stream.
On an iOS device, new photos you take will be automatically uploaded to your photo stream when you leave the Camera app and are connected to Wi-Fi. Note: My Photo Stream does not push photos over cellular connections.
On your Mac, any new photos you import to iPhoto or Aperture will begin uploading automatically when you have a Wi-Fi or Ethernet connection. Or, you can change your iPhoto or Aperture preferences so that only photos you manually add to My Photo Stream are uploaded.
On a PC with iCloud Control Panel 2.0 or later, open a Windows Explorer window. Select Photo Stream under Favorites. Open My Photo Stream. Click the "Add photos" button. Select photos to import to My Photo Stream, and then click Open.
You can get them to reappear on your iPhone by restoring it from backup or by re-enabling iCloud and the Photo Stream.