Internet of Things (IoT) becomes vital source of converting things into smart, including smart homes, smart cities, smart industries etc. Internet of things have the ability to connect billions of things at the same time, which seeks to develop information sharing requirements that improve our daily lives. By seeing things on the Internet, traditional devices become intelligent and independent, and this vision becomes real and realistic. The Blockchain appears a great source of providing security to new era technological applications. The high growth of IoT based smart applications have high demand of security to manage and maintain the IoT based application’s data safety, security integrity, and authentication. The merger of both technologies may provide our secure security solutions. This research explores the Internet of things security solutions by integrating IoT applications with blockchain. The research initially focused on the blockchain basics, types, design for Internet of things applications. Further we elaborate the several challenges and issue of BIoT applications linked to the energy efficiency, security, privacy, throughput, latency, block size, bandwidth, usability, multi chain management, versioning, forks, autonomy and enforcement. Finally, we explore the future directions of blockchain for the internet of things. The literaturebased results showed, that the integration of Blockchain with Internet of things provides significant solutions of security and privacy to IoT based application.