You can restrict user to view Joomla content using Content ACL app.
This app allows you to block any Joomla article, section or category from users as per their subscription plan.
Example1. You have five articles and out of them three are paid say Article1, Article2 and Article3 are paid articles.
You want your users will not be able to see those paid articles untill they purchase the required membership, like for accessing Article1 Plan1 needs to be subscribed, for Article2 Plan2 needs to subscribed and for Article3 Plan3 is required.
So you have to create three Content ACL app for this.
Step to achieve the scenario mentioned in the above example :
1. Create a Content ACL app for restricting Article1.
2. In parameters, select the type which you want to restrict, in this case select Article.
3. Now select the Joomla Article to be blocked, select Article1 in this case.
4. Attach the required plan with this app in Plan section of the app, in the example Plan1 is required for accessing Article1.
5. Repeat the above steps for Article2 and Article3.
The same process needs to be followed for restricting Joomla categories and sections.
Now at front view, users who are not subscribed to Plan1 will not be able to access Article1 completely. "Subscribe Plan to read more" link will appear in place of the read more link in the article. If no read more link exist in the article then content will be visible to users even though restriction is applied. Intro text of the articles will not be blocked unless you put a read-more link at the starting of the article.
The below screen-shot represents how Article1 will be displayed to a non-subscriber of Plan1.
When to Use
Content Hider can also be used to hide article's selected contents from unsubscribed users.