Most people learning to play a musical instrument practice alone.
When you practice with a teacher or with your friends, they can give you advice about your playing and you can identify the problems you need to work on. But when you practice alone, it's much more difficult to see your playing objectively.
That's when "Music Practice Tool" is really invaluable.
You can control the metronome, tuner and recorder all from the same screen, which means that as well as checking your tempo and tuning as you play, you can also directly record your playing. By listening to your recording as soon as you finish playing, you can get an objective impression of your performance.