I know how it is to lose important files stored on your Phone, trust me i have been there and it made me start to think if there is a recycle bin just like the one on pc which you can use to recover deleted files and i found one which is

Dumpster:Dumpster works just like the recycle bin on your mac, linux or windows desktop computer. Dumpster’s recovery ability is the perfect complementary cloud backup tool (Dropbox, Google Drive, Microsoft OneDrive). Completely eliminating the need to constantly backup your data. Dumpster gives you the ability to recover accidently deleted content including images, vids, audio, pdf, zip, mp3, mp4, ppt, doc, avi, mpg, jpg, rar and all common file types.And also you can recover apps unistalled, can you believe that. And one great thing about this app is that it doesn't require root. It eliminates the fear of you or anyone else mistakenly deleting your files.

You can search it on Google play store but if you want the link to download it ,here is the link to download it

http://www12.zippyshare.com/d/hNLKb0YC/1113296/com.baloota.dumpster-1.1.117.5427-APK4Fun.com.apk