Music Speed Changer has a tag editor that can be used to edit both album and track info. The tag editor can be opened from within the music editor as well as from within any of the the library tabs through the track or album menus.
Editing Track Art
Open the Track Menu
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Select Tag editor
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In the tag editor view you can edit the track Art, Title, Album, Artist, Genre, Year, and Track index by tapping the text or picture
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Save your changes by tapping the save button
Editing Album Art
Open the Track Menu
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Select Tag editor
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In the tag editor view you can edit the album Art, Album title, Album artist, Genre, and Year by tapping the text or picture
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Save your changes by tapping the save button