Abstract: One of most actively pursued current Blockchain-related use case has been the Internet of Things (IoTs). The three prominent reasons being: M2M Payments, Securing Identity of Things and automating the execution of processes. But the reality is that the Blockchain & IoT technologies aren't ready to be in production yet, mainly because of two limitations in current models: scalability and transaction fees. With the number of connected IoT devices estimated to reach 50 billion in coming years, ability to perform micro-transactions between these devices is a major issue. In comes IOTA, mainly designed to tackle the problem of transactional settlement for IoT. It is based on Directed Acyclic Graphs and relates scalability in direct proportion to number of transactions in the network without having any provision of incentivized mining and subsequently transaction fees. In this UGP, we study about the underlying details of Tangle which is the new distributed ledger architecture based on DAGs, transaction complexity involving tip selection algorithm from weighted random walks, the role of full nodes in IOTA, tackling the double spending problem in this mesh net and the newly introduced trinary hash functions and machinery which makes this technology quantum immune. We also employ the Tangle to build a web application named Energiota to demonstrate billing in the associated cryptocurrency in a private test-net which involves around 25 different seeds. We also present the concept of attaching transactions to the mesh net and the role of Coordinator for our scheme.