title_body: Convert an Android app which is actually an ebook to a pdf file?
upvoted_answer: Neither of the apps that you linked to are ebooks, in the description for LeetCode Cracker it even states that it is reading the data from GitHub which is why it requires an internet connection to view the content. The second app links to the GitHub repository that the problems and solutions are based on, https://github.com/FreeTymeKiyan/LeetCode-Sol-Res .
  
  These are not ebooks, they are collections of content put together in an app that may present themselves as something that resembles a book. To convert them to ebooks you would be best off taking the content from the GitHub repositories and making an EPUB or PDF out of them.
  
  The other option is to get a Chrome Book (or other device running ChromeOS) so that you can run Android applications like these from a laptop. Google has more information about running Android apps on ChromeOS here.