Of course, you can use another way to talk for free.
If there is no money on your phone, it remains only to find the one on whose phone they are. It is enough to approach a person on the street, and ask him a phone to make a call, while invent a qualitative reason . It is advisable to ask those people who are currently communicating on the phone. But this method is better to use not very often for a wave of understandable reasons.