Docomo is one of the leading network service providing company. It has some pros and cons.
Pros: The internet, sms plans are less compare to other service provider.
For smart phone there is an app for getting free docomo minutes.
Cons: Sometimes they automatically active some services and deduct money from account.In some areas network also not available.
Due to network problem if some one calls you then voice gets breaks in communication.
Try to improve your service guys!!