Development concept and feature list for binary option trading platform

We would like to develop a binary option trading platform like [login to view URL] (only binary options, not digital options, CFD, crypto or forex). We need a technology concept that focuses on preexisting and available backends (trade gateway, history server, trade server, management of user, trades, risk management, documents of traders, payment module) and other support software (e.g. CRM, Zendesk) but gives us the opportunity to develop our own front end (including front end trader's room). We believe the front end should be on the basis of Javascript-/HTML5, but are open for suggestions. From the trading platform like iqoption a feature list should be compiled as basis for the evaluation (trading platform and all account management features in the front end). Also define the necessary features for the backend and supporting systems. To do that you need to open a free account with iqoption. The concept should describe in detail the components, technology used and give a rough estimate on the cost for the individual development. It should also analyze competing applications for the back end and support functions. To be able to prepare the concept you need to have experience with binary option trading platforms and all the necessary requirements. Please provide references on projects related to binary or cfd trading platforms.