For developers, the Flippy module which i mentioned might be not flexible enough.
Drupal 7 – Display Previous and Next node links on node view using Flippy module
Then you could consider another module called Previous/Next API. With this module, you can add the previous and next node links in any preprocess functions, template.php or module files using the API functions provided by this module.
Another advantage is that it caches all the links in its own database table which could speed up the query and this also reduces the database loading. Let’s see how this module work.
Continue reading Drupal 7 – Get the prev and next node ID using Previous/Next API