I would just set metadata or set an annotation.
But I'm curious how would determine which page is the last one?
Are you gonna do that on every page load?

yes , i'm gonna do that on every page load

save and overwrite so i will get the last visited page

will it be  a problem ?

Don't think so, but I think there are more efficient ways of tracking a user.

You could look at something like Mautic, there is an elgg plugin somewhere on github for Mautic.
It gives you a lot more options, is more scalable and you can track every user and what he has done.
I looked at it briefly months back and I liked it a lot.
 

hmm ithink use Mautic plugin is not necessary for my web, now .

i just want to get the last visited page of my user,

okay i will use annotation (like what you said)

 create_annotation ($entity_guid, $name, $value, $value_type= '', $owner_guid=0, $access_id=ACCESS_PRIVATE)

what should the code be like ?

create_annotation($user->guid, 'lastvisitedpage', $_SERVER['REQUEST_URI']);

You will get 'a lot' of annotations if it's storing every pagevisit of every user.

You will get 'a lot' of annotations if it's storing every pagevisit of every user.

what's the worst if i get a lot of annotations ?

I honestly don't know, I'm sure there are better experts to answer your question then I, but you 'could' do something like this, to store only the last 10 annotation and only update the oldest one:
But again, I don't know if this is the most efficient way to do this.

nevermind

I'm thinking updating isn't a good approach here, it might be better to just delete the oldest one and create a new one, just thinking with you...

that would be this then:

$user_guid = elgg_get_logged_in_user_guid()
$count = (int)elgg_get_annotations(array(
		'annotation_names' => array('lastvisitedpage'),
		'annotation_owner_guids' => array($user_guid),
		'count' => true,
	));
   if ($count > 10) {
       $visitedpages = elgg_get_annotations(array(
		'annotation_names' => array('lastvisitedpage'),
		'annotation_owner_guids' => array($user_guid),
	));
       elgg_delete_annotation_by_id($visited_pages[0]->id) 	
   }
create_annotation($user_guid, 'lastvisitedpage', $_SERVER['REQUEST_URI']);

and in the case you only want the latest one (I thought I read somewhere you wanted the last 10 visits, but can't find it anymore)
It would be:

$user_guid = elgg_get_logged_in_user_guid();
if (elgg_annotation_exists($user_guid,'lastvisitedpage',$owner_guid = null)) {
	$annotation = elgg_get_annotations(array(
		'annotation_names' => array('lastvisitedpage'),
		'annotation_owner_guids' => array($user_guid),
		'limit' => 1,
	));
	update_annotation($annotation[0]->id, 'lastvisitedpage', $_SERVER['REQUEST_URI']);
} else {
	create_annotation($user_guid, 'lastvisitedpage', $_SERVER['REQUEST_URI']);
}

But metadata would be much easier then, and you overwrite it on every visit:

$user = elgg_get_logged_in_user_entity();
$user->lastpage = $_SERVER['REQUEST_URI'];

okay it's too complicated for me what if i just use:

$value = elgg_get_plugin_setting('lastvisited',$userguid,'lastvisited');

$url = $entity->getURL();

array_push($value,$url)

elgg_set_plugin_setting('lastvisited',$value,'lastvisited');

advantage: no too many annotation

but i don't know the possible disadvantages . if there is no disadvantages i will use this one.