This app was mentioned in 3 comments, with an average of 4.67 upvotes
Yup, this one, precisely.
The random button and the "mark as read" feature made it very convenient, but it has a "payoff" as it tends to show a buggy version of some of the articles: strikethrough text appear as normal, tables are never shown (a huge drawback for SCPs like 1733) and special SCPs doesn't appear at all.
If you can deal with it, though, I can recommend it. I just can't switch to any other SCP reader app.
This one. A bit buggy but I can deal with it.