Build a modified Telegram app

Looking to develop a modified Telegram APP (for Android iOS and Windows) Concept: Safe Telegram - that will not have bots and channels and cannot search for them. I want to create our own version of the Telegram app ([login to view URL]) that will not have bots or channels and cannot search or connect to bots and channels Also we would like to have the option of allowing some groups for users that request, so will need a web back end to see and manage the customers and to allow certain things that they do want (For example a parent wants child to have telegram but not to have porn bots or channels but yes the family or friends group).. - It must be able to work with and based on the regular Telegram (connect to users of the regular Telegram) - Must be able to take payments (paid app) - Must have web back end to manage customers - Must be compatible with Android iOS and Windows computer (all sizes and latest versions) More ideas and originality is welcomed.