Cellular IoT is arriving in daily IoT business. The Telco providers all over the world are deploying their NB-IoT and/or CAT M1 networks. In Germany, Deutsche Telekom has been the first mover and started NB-IoT deployment in Juni 2017, Vodafone has followed in August 2018. Still, the technology is young and questions need to be answered. mm1 Technology was one of the first companies to test and work within the Deutsche Telekom NB-IoT network and supported the integration into their Backend and Cloud system. This presentation will give an overwiew on the current NB-IoT situation in Germany, Europe and Worldwide and will share insights from our prototypes and developments with focus on energy efficient approaches and flexible integration into multiple cloud systems.