A free program for Android, by Cometdocs.com Inc..

The best thing about this app is that you don't need to install anything. All you need is an internet connection and this app is ready to use. The first thing you need to do is to log in with your Dropbox, Google Drive, or OneDrive account. This way you can import all the files from these cloud services directly to the app and you don't need to download them first.

Once the documents are in the app, you can select which pages you want to remove and just tap "Remove" in the upper left corner. You can also select all the pages at once and remove them all at once.