The performance of the stock market affects us all and good times are ahead when it is up, but a crash can be serious for the economy. Configure the Stocks app on the iPhone Today screen.

The Stocks app on the iPhone used to be an irritation. It had a limited set of features and it was stuck on the home screen and could not be removed if you did not want it. Times have changed and the latest version of the Stocks app is both useful and more informative.

It can also be deleted in the usual way, press and hold until it wiggles, if you really don't want it. However, you might want to keep it to keep track of all the ups and downs of the stock markets and share prices. With the fortunes of internet companies and old style bricks and mortar businesses changing on a daily basis, the Stocks app has become an essential source of news.

It actually is a source of news and if you open the Stocks app and pull up the news from the bottom of the screen, it shows stories from many sources, like the Apple News app and other places. It is customised to your region of the world and shows the news stories that affect you. Even if you don't own shares, you should use the Stocks app to follow the news.

1 Add the Stocks widget

The iPhone's Today screen can show useful information from widgets. Not all apps have widgets, but the Apple Stocks app does and it is a great way to keep an eye on your favourite companies. On the iPhone home screen, swipe right to show the Today screen and tap Edit at the bottom - you may need to swipe up to see it if there are already lots of widgets on the screen.

Find the Stocks widget in the list and tap the plus button to add it. If you have more than one widget on the Today screen, press and drag the three bars icon on the right of a widget to move it up or down. Change the order so your favorites are first. Tap Done in the top right corner when you have finished.

2 Stocks on Today

The Stocks app shows the current value of a couple of stock markets or companies, but they may not be ones you are interested in. However, you can choose the companies and markets you want to follow by opening the Stocks app.

3 Edit the default stocks

Open the Stocks app and a small number of items are displayed, which may or may not interest you. Each country has its own defaults, so your list may be different to mine. It is easily changed though. Press the Edit link in the top right corner of the screen to edit the list.

4 Search for companies

Companies and markets are known by their symbols. Some are obvious, but many are not and Apple is AAPL, not APPL as you might expect. If there is a .L or other .something, it refers to the stock market, so APGN.L is on the London stock market for example. Sometimes the stock market is displayed beside the symbol, so AAPL is on Nasdaq for example.

The Stocks app is pretty good at finding companies if you enter their name into the search box at the top. When you find a company or market you want to follow, press it.

5 View share prices and charts

A screen full of information and news stories is displayed and it is both fascinating and useful You can see the current price and a chart showing the price changes over the the last dat, week, month, 3, 6, 12 and 24 months. The chart is green when the the price is rising and red when it is falling.

That is useful, but what we are interested in is customizing the widget on the Today screen. Tap Add to Watchlist to add this item.

6 Customize the Watchlist

The Watchlist is displayed after adding an item. Press the red minus icon to remove the items you do not want to see. Press, hold and drag the three bars icon to move items up or down the list. The widget has expanded and collapsed display modes and only the top two items are shown in collapsed view, so drag your favourites to the top.

Press the plus button at the bottom of the screen to add more stocks or markets and press Done in the top right corner when you have finished.

7 View your new stocks list

The new Stocks home screen now shows the stocks and markets you are interested in and there is the current price, the change in price (red or green) and a mini chart showing recent movement.

8 View Stocks on the Today screen

Quit the Stocks app and return to the home screen to see the changes to the Stocks widget. It shows the top two items in the Stocks Watchlist in collapsed view, but tap the > in the top right corner of the widget to expand it and show all the Watchlist items. Tap an item to open the Stocks app with that item's detailed information screen.