Regardless if you use Apple or Android devices, you can always use the free Adobe Scan app to scan paper documents to clean and neat PDF. Please refer to the following video tutorial for how to download and use the app. Fullscreen viewing is suggested if you are reading this webpage on your phone.
If you use Apple devices:
If you use Android devices:
Other than the free Adobe Scan app, we also recommend a paid app that is better to do the job. If you use Apple devices please click here for the video tutorial; if you use Android devices please click here for the tutorial.