First of all let’s mention that Niger is officially a religious free country with this freedom, along with the complete separation between religion and State, protected and defined by the Constitution of 2010. It is very rare to see any sort of religious persecution and Niger is ranked low (#50) in the countries where Christians may be persecuted for their faith.
80% of the population practices a faith attached to Islam. 59% are Suni, 20% do not attach a denomination to their faith, 7% are Shi’a and 6% practice Ahmadiyya. The remaining 20% of the population are Christians that have turned to the faith out of the French influence and the missionaries that came along to preach.
For the Muslims the story is a bit different. Islam was brought in through the trans-Saharan trade practices, the expansion of the Tuareg from the North and the similar expansion of the Songhai Empire from the West. However the practices of Islam observed in other religious states do not exist here. Although it is very rare for married couples to divorce, there is no noticeable polygamy (i.e. no charems) and the women do not cover their faces or hair if they do not want to. Another differentiation from the usual Islam practices is that the people can consume alcohol.
There is still a small number of people, mostly among the Hausa ethnic group that still practice the pre-Islamic local religious beliefs and mostly in small communities. There are also some Muslim communities called synthetic that still hold festivals from their pre-Islamic era.