PDF Preparation
Before you upload your assignment to Gradescope, you need to save it as a PDF file. The assignment must be prepared as a single file (and not e.g. split into one file per page).
It is easy to produce such PDF file from handwritten pages using a smartphone, and there are many apps both for iOS and Android that can accomplish this. See below for a few recommendation of apps which are freely available and ad-free, with links to instructions how to use them.
Android
Microsoft Office Lens for Android available from the Google Play Store
Google Drive available from the Google Play Store.
iOS
Microsoft Office Lens for iOS available from the Apple App Store
Apple Notes. This app is factory installed on all iPhones and iPads, but it is also available from the Apple App Store.