[android] Select multiple images from android gallery

I hope this answer isn't late. Because the gallery widget doesn't support multiple selection by default, but you can custom the gridview which accepted your multiselect intent. The other option is to extend the gallery view and add in your own code to allow multiple selection.
This is the simple library can do it: https://github.com/luminousman/MultipleImagePick

Update:
From @ilsy's comment, CustomGalleryActivity in this library use manageQuery, which is deprecated, so it should be changed to getContentResolver().query() and cursor.close() like this answer