If I have, say, a long paragraph of text and there are certain words that I want the user to be able to tap to reveal a lot of extra information but within the same page, how do I do it ? I am aware of how the Wikipedia app allows users to click on a specific term in an article for a small (menu?) to pop-up with a button that takes user to the article for that term. But this makes the article behind inaccessible unless user presses back button and I would like the extra information to be revealed without displacing or rather covering up the original block of text from the screen.
Also, how should the user know that this piece of text can be clicked to reveal extra information. (Making the font blue for the word, while suitable for the web, doesn't exactly look user-friendly in an app, in my opinion!)
You can have tool tip on a word I think this will be the only idea to display the short description of one word. But ya you can direct the user by highlighting the word. Fro example you can give blink effect on the word which have short description. I have just highlighted the word here with Red color you can give effect on the word like constant changing the color of the word.
I attached two screens below. one having normal paragraph and other having info when user hover the mouse cursor on the word.