Ethereum network now plays host to over 1200 decentralised applications (DApps), and yet, their adoption has thus far been limited to those within the crypto-community. Thankfully, ECOMI are developing an intuitive and simple to use DApp marketplace, so that the general public can enjoy the benefits of distributed ledger technology without consciously realising it. Decentralised applications are those which have their backend code running on a decentralised, peer-to-peer network, such as Ethereum. Whereas traditional apps run on a centralised server, and are controlled by a singular/centralised entity.  DApps can use both decentralised storage and decentralised communication. By utilising peer-to-peer networks, and coupling them with the potential offered by smart contracts, we are effectively removing human interference from transactions and the transfer of data/information.

Understanding the difference between apps and DApps. Credit.
According to Johnston and Byington, a DApp has the following characteristics:

Tokens. These are necessary for both the use of the DApp, and as a reward for any contributions from users. The tokens should be generated according to a standard algorithm or set of criteria, for example, miners are rewarded in Bitcoin for confirming transactions. However, this is not the only set of criteria available for token generation, and some or all of a DApps tokens may be issued at the beginning of the operation.
The ability to adapt its protocol, in response to proposed improvements and feedback. HOWEVER, all changes must be decided by majority consensus of its users. Forks are one example of a change to protocol.
The DApp must be completely open-source and operate autonomously, with no single entity controlling the majority of its tokens. Furthermore, the operations, actions, and decisions of any DApp governing bodies must be cryptographically stored in a public, decentralised database such as a blockchain. In this way the development and operation of DApps remains transparent, with a record of all information and accountability readily available.
It is also important to note that DApps can run on their own blockchain, or can operate as protocols (their own system of governance and operation) on an existing blockchain. Whilst the systems between these DApps may vary, the basic rules and principles mentioned above are consistent, and the potential for applications almost endless.

Why DApps?
Even though apps have only been adopted since the smart phone became a thing, they are already dated technology. With growing concerns over identity fraud, data breaches of centralised servers, and the unauthorised collection of information (the Facebook/Cambridge Analytica scandle for example) there is a proven need for DApps that take the power out of centralised control.

In doing so, DApps create a system of:

Transparency
Open governance and adaptability- allowing the implementation of changes that are approved by the users, not a single entity.
Security- offered by the immutable ledger that is blockchain. Every user of a DApp strengthens the security of the wider ecosystem.
Community participation and incentivised use- by rewarding users with tokens, or providing a utility for the token, DApps have a verifiable value, allowing them to run without centralised control.

DApps have been the domain of coders, start-ups, fin-tech businesses and serious enthusiasts. ECOMI aims to streamline and simplify the way everyone else uses and interacts with DApps by creating the ECOMI DApp marketplace. Operating in a similar manner to Apples App Store, or Google Play for Android, the ECOMI App will not only provide access to ECOMI’s DApps (Wallet, Collect and Vault) but also creates a platform for third party developers to market their own DApps. By offering a mobile and desktop version, as well as browser extensions for some features, ECOMI aims to bring the benefits of DApps into the mainstream without making it an unfamiliar process
https://www.ecomi.com