As one of its daily deals, Yugster offers the factory-refurbished Unlocked Apple iPhone 4S 16GB Smartphone for GSM Networks in Black (pictured), model no. MD234LL/A, or White, model no. MD237LL/A, for $169.97 with free shipping. That's the lowest total price we could find for a refurb by $30, although we saw a refurb for $3 less three days ago (since expired). It's compatible with GSM networks such as AT&T, T-Mobile, and Vodafone; it can't be used with CDMA networks such as Verizon or Sprint.

Also available is the refurbished Unlocked Apple iPhone 4S 32GB Smartphone for GSM Networks in White for $179.97 with free shipping. That's another current low for a refurb by $40, although we saw a refurb for $3 less three days ago. A 90-day Apple warranty applies to both models. Both deals end today.