Hi chemitechniques,
Printing from the Android phone requires the Canon PRINT Inkjet/Selphy app, available for free from Google Play. Once installed, you will be able to both scan and print, and I have included full instructions for using the app HERE.
Printing from a Chromebook requires Google Cloud Print, and the PIXMA MG3120 can be set up as a classic printer. If you want to use your USB connected printer as a Classic Printer with Google Cloud Print, click here to go to the Google Cloud Print page. Follow any on-screen prompts.
A Google Account is required to use the printer as a Classic Printer with Google Cloud Print.
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