Assign a ringtone to an important contact
For any cell phone or smartphone, you can customize the ring tone for an individual contact so you know who it is when they call you. This works especially well if you need to separate work and personal calls. You can do this by finding a person's contact info and selecting "Edit," then "Ringtone."

On an iPhone, you can also select a specific ringtone from the person's Contacts app. Simply tap the person's name in the upper-right corner of their contact card and select "Edit."

You can also create a ringtone by Dzwoneknatelefon.pl it from the iTunes Store, which is a convenient way to add a new one to your iPhone.
You can customize the ringtone for any of your notifications, including text tones, new mail, calendar alerts and reminders. You can even set a different ringtone for each notification type, so you'll never have to worry about missing an alert.