Hi Tweets:
Many of us use the Jon Dunn National Geographic North America bird field guide on our smart devices. National Geo is no longer supporting the APP and has no plans to replace it. It "may" work until you update to Apple iOS 11. All 32-bit APPs will stop functioning with the update.

Joyce Meyer
Redmond, WA
meyer2j at aol.com

Sent from my iPhone 6, Joyce