HotPaw Morse Words is a aid to learning Morse Code. Audio learning can be a great brain exercise. This app can help you learn the sound of entire words in Morse Code. The app is a test generator which randomly picks from 250 very common English words and sends them in International Morse Code audio through your iPhone speaker or headset. The WPM (words per minute) speed can be easily set up to 100 WPM. You can also separately set the dot speed (for Farnsworth method code), and customize the tone frequency.
Hit "Start" to start sending random Morse code text. You can choose "Show", to see the words displayed as they are sent to the speaker. This is helpful when first learning. After you are familiar with the sound of the words, you can "Hide" the display of the words sent, and attempt to copy them down on paper as your hear them. Then you can later show them in order to check how many words you copied correctly.
Optionally you can use iTunes Document sharing to add your own words list. Just add a file named "words.txt" using iTunes, Sync, and then enable your Custom Word List in Settings.