The Internet of Things (IoT) is the network of things (physical devices, vehicles, home appliances, and other items embedded with electronics, software, sensors, actuators) connected through internet which enables these things to exchange data. This creates opportunities for more direct integration of the physical world into computer-based systems, resulting in efficiency improvements, economic benefits, and reduced human exertions.
In simple terms we can say IoT is a system of things integrated with sensors, softwares, electronics which are connected to each other & can exchange data or Information with other connected devices.
The IoT soultions are spread across wide areas and some are listed below
IoT devices part of home automations like lighting, temperature control, air conditioning, security systems etc.
IoT devices used in corporate & business
Monitoring & controlling of infrastructure like bridges, railways, roads, traffic etc.
Integration in manufacturing area with sensors for identification, communication, tracking etc is improving the efficiency of manufacturing area. Example like opening the door automatically when truck comes.
There are numerous IoT applications in farming such as collecting data on temperature, rainfall, humidity, wind speed, pest infestation, and soil content. This data can be used to automate farming techniques, take informed decisions to improve quality and quantity, minimize risk and waste, and reduce effort required to manage crops.
IoT solutions for environmental protection , monitoring rivers, water quality , forest area etc.
Lot of power sources can be connected & can communicate each other for better utilization of power.
Medical & Healthcare
IoT devices for health monitorings & other activities in hospitals, health centers.
The number of IoT devices increased 31% year-over-year to 8.4 billion in 2017 and it is estimated that there will be 30 billion devices by 2020
Some of the major IoT platforms are listed below
Google Cloud IoT
AWS IoT Core
Microsoft Azure IoT
IBM Watson IoT
Bosch IoT Suite
Oracle IoT cloud platform
Above has given you IoT Platform companies list , To more about Top IoT platform Companies features refer http://www.thetips4you.com/iot-platform-companies/
There are free IoT platforms available also like
Kaa IoT platform
Also for Project management topics kindly refer the articles link1,link2,link3,link4,link5,link6.