Indian English is a recognized dialect of English, just like British Received Pronunciation (RP, or BBC English) or Australian English, or Standard American. It has a lot of distinctive pronunciations, some distinctive syntax, and quite a bit of lexical variation. "Indian English" encompasses words derived from Hindi and other languages on the subcontinent (e.g., ayah, babu, dacoit, lakh, nawab, and wallah), as well as English words that have developed their own history in India like revert. You can hear examples of Indian English spoken here http://ice-corpora.net/ice/ind1.mp2