@Multipart
@POST("index.php")
Call<ResponseModel> uploadImage(@Part("json_field") String description, @Part("image") RequestBody image);

if (Build.VERSION.SDK_INT <=19){
     Intent intent = new Intent();
     intent.setType("image/jpeg");
     intent.setAction(Intent.ACTION_GET_CONTENT);
     startActivityForResult(Intent.createChooser(intent, "Выбор изоброжения"),100);
} else {
     Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
     intent.addCategory(Intent.CATEGORY_OPENABLE);
     intent.setType("image/*");
     startActivityForResult(intent, 100);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == 100 && resultCode == RESULT_OK){
        Uri imageUri = data.getData();
        File file = new File(String.valueOf(imageUri));


        RequestBody requestFile = RequestBody.create(imageType, file);

        uploadData(requestFile);
    }
}

/content:/media/external/images/media/31037: open failed: ENOENT (No such file or directory)