iCloud ! If you didn't back anything up, then it probably won't help ! But start backing everything up into your e-mail or iCloud account ! In case you loose your data again you have all your belongings saved and you can have them back on your phone ! Hope this helped ! ;D
You can recover your data if you had recovery software on your device or the computer. If you have it on the computer, just connect your iPhone to the computer and run the recovery process. However, if you do not have any product or did not back it up, it may be hard to recover your stuff. Otherwise, you can contact any data recovery companies in your location for further assistance.