There are a number of mobile apps that you can install on both Android and iOS phones. These cover a majority of topic areas from plants and trees to insects and animals.
I have recently been using a few of these whilst out and about and in the garden. They are okay, but do not always get things right so its always worth double checking an id of something if you are unsure.
A good app to use if you are starting out with one is Seek which has a number of challenges for you to try and complete by finding different nature and wildlife around.
As you can see from the picture though they can’t always be reliable!
Would I trust an app whilst out say foraging? Well not as my primary means of ID.
That said, these apps do help you get out and enjoy nature, so download one today and see what you can identify.