You cannot use the MuseScore app/website to create scores. There is a free MuseScore PROGRAM that allows you to notate scores. Click the download button on the home page to install the program.
To answer the question another way: if you really want to use a mobile device to create scores and then use those scores within the MuseScore ecosystem (eg, do further editing in MuseScore on your computer, upload to musescore.com or otherwise share with other MuseScore users, view/play using the MuseScore mobile apps, etc), you could download another program that does allow editing on your particular mobile device (eg, Notion for iPad) and then export to MusicXML, then import that into MuseScore on your computer. I've done this sort of thing on occasion. You could also use something like Chrome Remote Desktop to allow your mobile device to access your computer running MuseScore - probably a better solution if your computer is always on and you have an internet connection when you want to work. Or, something like the rollApp service, which allows you to run MuseScore remotely via their servers, and you can save your work to Google Drive.
Comments
Welcome. Currently it is not possible, see: https://musescore.org/en/node/88781
In reply to Welcome. Currently it is not… by Shoichi
You cannot use the MuseScore app/website to create scores. There is a free MuseScore PROGRAM that allows you to notate scores. Click the download button on the home page to install the program.
In reply to You cannot use the MuseScore… by Quinn Ouyang
@Meh Inc. The mobile versions (Android and IPhone) are for playback only. They won't allow creating new scores.
To answer the question another way: if you really want to use a mobile device to create scores and then use those scores within the MuseScore ecosystem (eg, do further editing in MuseScore on your computer, upload to musescore.com or otherwise share with other MuseScore users, view/play using the MuseScore mobile apps, etc), you could download another program that does allow editing on your particular mobile device (eg, Notion for iPad) and then export to MusicXML, then import that into MuseScore on your computer. I've done this sort of thing on occasion. You could also use something like Chrome Remote Desktop to allow your mobile device to access your computer running MuseScore - probably a better solution if your computer is always on and you have an internet connection when you want to work. Or, something like the rollApp service, which allows you to run MuseScore remotely via their servers, and you can save your work to Google Drive.