How to Recover Deleted Data from Android Internal Memory
"I've literally try all software in the world, yet no a single one can recover deleted files from my Samsung Galaxy S4.Can any one tell me how to do it?"
Actually, I myself have also had such a problem. Later, I learn that internal memory does not mount as a drive like external memory does and that usually Android recovery tools can only restore things from mounted memory location—SD Card. But, Android Data Recovery can easily solve it. My phone is Samsung Galaxy S3, based on Android 4.0 though I assume this should work for most Android phones of most Android OS's, including Android 4.3 and 4.4.
1.Android Data Recovery, which is a professional program designed for retrieving lost contacts, messages, WhatsApp history, pictures, music and videos from Android internal memory and also external memory.
2.A USB cable.
3.A computer (This app also has a version for mac. Since the process is more or less the same as in Win7, I will only do it under Windows.)
1.Stop using your phone right away. 'cause every time you add a new file may mean that the picture of a deleted file is taken. In other words, there is no coming back when the data are overwritten.
2.Make sure that your device is left with power of over 20% so that it won't shut down during the process.
Now we should begin our work by downloading and installing Android Data Recovery.
Android Internal Memory Data Recovery
Step 1. Connect Android to Computer and Enable USB Debugging
When you launch Android Data Recovery, a window like this should be seen. Connect the two as is told.
Step 2. Enable USB Debugging
If you don't know what USB debugging is, you probably have not enabled it. Then look at this picture, which clearly depicts how it is done.
1.For Android 2.3 or earlier: Enter "Settings" < Click "Applications" < Click "Development" < Check "USB debugging"
2.For Android 3.0 to 4.1: Enter "Settings" < Click "Developer options" < Check "USB debugging"
3.For Android 4.2 or newer: Enter "Settings" < Click "About Phone" < Tap "Build number" for several times until getting a note "You are under developer mode" < Back to "Settings" < Click "Developer options" < Check "USB debugging"
Step 3. Choose Which Kind of File to Be Scanned and in What Mode to Do It
When you finish step 3, the software will make you decide what to scan. Check whichever you want as long as it suits you. And click Next.
Then, select one of the modes. "Scan for deleted files" is recommended, because, apparently, it only search for lost data. Press Next again. (The button Back is for you to return to the last step in case any mistake happens.)
Step 4. Allow Superuser Request and Begin Scanning
Now we've come to a point that Android Data Recovery should be grant authority to operate on a rooted phone. Tap Allow on your Android until it no longer shows up. After that, press the Start button on your computer to get going.
Step 5. Preview and Recover Files From Internal Memory
The result will be shown in red and black. View the content first to see if they are what you want. And you may tick the red ones only, which stand for your lost data. Of course, it is your call to choose them all. Recover should be clicked to finish the scanning process.
When all is done, the lost contents will be saved in your PC.
Note: Do a backup regularly. It really helps reduce your loss. How to do it? Android Manager should be of good use.