This is potential a very MINOR bug(?) in the backend UI. The applications->install UI complains that SOCIAL_MEDIA . '/fields' and SOCIAL_MEDIA . '/applications' directories are not writable.
Currently the following directories are being used to store apps: SOCIAL_MEDIA . '/apps/fields' and SOCIAL_MEDIA . '/apps/user'

Version 1.3.1
File: /administrator/components/com_easysocial/models/apps.php
Code: lines 441/442

// Get a list of folders.
$folders = array(
$jConfig->getValue( 'tmp_path' ),
SOCIAL_MEDIA,
SOCIAL_MEDIA . '/fields',
SOCIAL_MEDIA . '/applications'
);