This app specializes in finding images that are similar enough to be considered duplicates. Unnecessary images can thus be deleted to free up space on your device.
On launch, the app searches for all of your images. All you have to do is choose the directories to process to obtain the groups of photos presenting the same views or subjects. You can then choose which images to delete or ask the application to do it automatically.
This application uses the advanced algorithms and characteristics of the Panaustick application by the same author (http://en.panaustik.com). Therefore, it does not give false positives. It can process a large number of images quickly. It detects duplicate images even if they are not the same size, have different orientations or lighting conditions, are more or less sharp...
Note: The app analyzes images like a human eye would to detect similarities between photos. For this, it uses advanced algorithms that require a lot of calculations. The initial work may seem relatively slow although it is possible to process 2-5 pictures per second depending on the speed of your device. Fortunately, the results of some intermediate calculations can be saved. Thus, after the first execution, the calculations will be much faster.
If you're looking for a less specific app to find duplicates of any file type, you can try FileDup (https://play.google.com/store/apps/details?id=com.panaustik.filedup) which searches for exact duplicates and is therefore much faster.
This completely free application has no restrictions, does not collect any personal data and is guaranteed without 'tracker'.