Related Clues:

• Exchange between cell mates?
• Phone-to-phone message
• Something bound to sell?
• 'Philosophy is common sense with big ___' (James Madison)
• Reading volume
• Item in a bibliophile's collection
• Kind of book, or what's in it
• Lyricist's concern
• Spot for a jacket
• Sent a message to main body
• It may be skillfully created by one who's all thumbs
• Message that may include emoji
• 'omg' or 'lol,' say
• Small-screen reading
• Mobile message