Choosing a birding field guide brings up the never ending question of Photos vs Drawings. You can find lots of pros and cons on the internet. For me I like Photo based guides because they show real life examples. I particularly like the regional guides where plumage may vary from the standard. I like Drawing based guides because they can show species variations and are not reliant on good lighting. I have an edition of a drawing based field guide where the printer darkened the images making the birds look darker than they are in the field. Other printings/editions did not have this error.
Now let’s bring up the topic of birding apps. Are they better than the typical paper field guide? Sorry, I’m not going to make a clear declaration on this one either. I love how I can search for specific species or terms in an app. I love that it includes so much more information such as bird calls, more images, cross links to similar species by coloration or call, etc. The additional material is a marvel.
So what do I use personally? Sibley. I use either Big Sibley (Sibley Guide to Birds) or Little Sibley (Sibley Field Guide to Birds of Western North America)
However you may also find in my car or scattered around the house a number of general guides including the classics: The Kaufman Field Guide to the Birds of North America, and The Peterson Field Guide to Birds of Western North America. I also have a plethora of location specific guides such as Birdfinding in British Columbia, Birding Colorado, and Birds of Idaho. And let’s not forget the species specific guides like the Warbler Guide, Hawks in Flight, and Gulls Simplified
I also have a number of apps on my phone. The one I use the most is iBird. But I’ve also downloaded and used the Audubon, Sibley Birds, eBird, and Merlin apps.
So what do I recommend? I believe you must have a copy of the Sibley field guide in paper. After that it’s up to you and how you think/learn. Ask yourself how well you hold images in your head. Are you able to extrapolate from a photo that is a specific individual to the variety of individuals that may be similar? Do you prefer a set of drawings showing the differences but not the bird in situ? Or maybe you are like me and want/need all of the options.
I will admit that I need the field guides less these days because I know the birds in my location fairly well. But I still keep it with me just in case.
The Audubon site has a discussion of this very topic along with recommendations. See: https://www.audubon.org/news/what-bird-guide-best-you. After reading this I now have a couple more books on my wishlist: The Crossley Guide, The National Geographic Field Guide and possibly Rare Birds of North America. — Jenny