is there an app to identify trees?

If you are identifying trees in the UK

The Woodland Trust Tree ID app is free and runs on iPhone and Android. It identifies the UK's native and common non-native trees using leaves, bark, twigs, buds, flowers or fruit, so you can use whichever part of the tree you can see at the time of year you are looking.

The limit is scope. It covers UK trees, so a tree from another country may not be in it. The Woodland Trust's page does not say how many species it includes, so we cannot tell you how deep the coverage goes.

If you want a free photo identifier that is not limited to one country

Pl@ntNet identifies plants from photos. It has app store links for iOS and Android plus an online version, and its home page lists 84,710 species across 77 floras. It is a citizen science project, and the site asks for donations to keep it open and free to everyone.

The trade-off is focus. It is a general plant identifier, and its home page does not single out trees or make claims about accuracy. Check any suggestion it gives you against a description of the tree.

If you want a no-account app for general nature spotting

Seek by iNaturalist is a camera app that uses image recognition to identify plants, animals and fungi around you. Its page says no registration is involved and no user data is collected. It is available on iOS and Android.

The page describes plants and wildlife in general and does not name trees. It also does not state a price, so whether it is free is not verified.

If you are in North America and prefer a leaf key to a photo

The Arbor Day Foundation's tree identification tool is an illustrated, step-by-step process for identifying trees by their leaves, organised by region. The page states no price for it, and it suits North American trees.

There is no photo recognition. You follow the steps by hand, which takes longer than taking a picture but shows you which features to look at, so it suits people who want to learn the trees. It is a website tool, and the page does not describe a mobile app.

When paying comes into it

The Woodland Trust app and Pl@ntNet are free on the pages we read, and the Arbor Day Foundation page states no price for its online tool, so paying does not look necessary to identify a tree. PictureThis is a plant identifier app and website with care guides, disease and toxicity information, and its home page shows tree entries such as Norway spruce and mango tree. That page offers "Try for Free" and "Download the App for Free" but gives no subscription prices, so its cost is not verified, and it does not say what the free version allows.

The descriptions are narrower than the names suggest. Seek's page covers plants and wildlife in general and never names trees. PictureThis is aimed mainly at gardeners and houseplants, even though its home page shows a few tree entries.

Pl@ntNet is a citizen science project that asks for donations to keep it open and free to everyone. The Woodland Trust app is for UK species, so check where your tree is growing before relying on it. The Arbor Day tool is a website, and its pocket field guide is a printed book sold separately, with no price seen.