DeviMahatyam/Durga Saptashati ("Glory of the Goddess")describes the Goddess as the supreme power and creator of the universe.
It contains 700 verses arranged into 13 chapters.
It describes the battle between good and evil, where the Devi manifesting as goddess Durga leads the forces of good against the demon Mahishasura.
The thirteen chapters are divided into three charitas or episodes. At the beginning of each episode a different presiding goddess is invoked.
It is part of the Markandeya Purana.
This app has all 13 chapters in English,Hindi,Telugu.