The best alternatives to Polarr 3.0 for iOS are Trueface, Unify, and Smile Snap!. If these 3 options don't work for you, we've listed a few more alternatives below.
What do you think of Polarr 3.0 for iOS?
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Featured by Apple under "Apps We Love Right Now". Unify lets you combine the best parts of your Apple Live Photos to create group pics that don't exist. Combine the best frames to create group pics where everyone looks good. Try free on the iOS App Store.