I'd recommend taking a look at iNaturalist: https://www.inaturalist.org/home

When you post observations, their AI does a great (though not perfect) job of identifying species. Works really well for birds, butterflies, does a generally good job on plants (tip: if it's flowering get the flower in the photo), and also is good with many wild mammals if you can get a decent photo. Not so good for many beetles, fungi, moss and other species where a photo's not really adequate for id. You post observations with time and location they have a map you can explore in many ways, and also there's an 'Explore' option that lets you see what wildlife are being reported in your area or an area you choose to explore.

Also the data from those observations is used by scientific researchers, so by using it you're contributing to citizen science.

edit to add: also it's free

'Seek' by iNaturalist is really good. Point your phone camera at an animal or plant, and it'll try to ID it

I’ve been using anki flash cards to learn birds in my local area. It works really well, in a few weeks I could identify a few score different birds.

I’ve also used Anki to learn some plants and insects.

Also, if you Reddit, subscribe to r/whatisthisbird (along with whatisthisbug and r/birding), and every day you’ll learn birds and bugs. I also do this with artwork as my random desktop background. I see it every day, so I can now recognize some paintings. I put no effort into learning, they’re just there and I pick it up passively! Should work with pics of birds.

I'm not sold on the plant ones. I saw a long thread on instagram of a botanist rubbishing on of the "recognise a plant via a photo" apps. I wish I could remember which one it was...

Bird Net has never let me down though (in Europe at least - not tried further afield).

eBird, iBird Pro (UK), BirdNet, Merlin, PlantNet, and iNaturalist are my go-to apps for general outdoors adventures and casual walks. I like snapping pictures and posting on iNaturalist because the community and citizen scientists will help you ID birds, reptiles, plants, flowers, insects, etc. iBird is great for bird ID from pictures and a library of sounds.

The pandemic also brought more awareness of my local flora and fauna for me as well.

I've found PictureThis to be great for identifying plants. They claim to cover 100+ countries. There's a premium version but I just opt out by hitting the Cancel button at top right of the screen. It's been able to ID plants from photos other people have taken (pointing at their phone).

Thanks everyone for the suggestions. Rather than reply to individual responses, I’ve upvoted them and look forward to trying out the suggestions.

On my walk this evening, I tried Bird Net and found it very intuitive to use. It successfully identified magpies (which I already recognised) and blackbirds (which I wasn’t sure about it).