AnkerDirect via Amazon offers its Anker Tempered Glass Screen Protector for iPhone 6 for $9.99. Coupon code "67SH8JNY" drops it to $5.99. Plus, Amazon Prime members bag free shipping. (Non-members can spend $35 to qualify for free shipping; otherwise it adds $6.22.) That's $14 off and the lowest total price we could find. It features an anti-smudge coating and has a hardness rating of 9H for scratch protection.

It's also available for the iPhone 6 Plus for $9.99. Apply coupon code "GO4T3PPD" to cut it to $7.99.