viewer (n.)

• acquirer
• addressee
• audience
• auditor
• beholder
• bystander
• consignee
• eyewitness
• gazer
• getter
• hearer
• holder
• kibitzer
• listener
• looker
• looker-on
• observer
• ogler
• onlooker
• payee
• perceiver
• percipient
• procurer
• receiver
• recipient
• seer
• spectator
• taker
• trustee
• watcher
• witness