Android App Developer

I wanna provide service to peoples. Like suppose you need anything like Grocery,Food,etc like anything you wanted at your place,, we’ll fulfill all the requirement whatever they need, so simply they open the request and submit it, So i need they could contact us through Live Chat and providing a toll-free number or any number. I need an App like front page suppose to be Dyanamic all the menu's button on front. ----------------------------- There will be 2 apps : 1 administration and 1 user . User will register using his mail I'd and password . User will get an option to view previous request and create new request. User can create a new request by filling 4-5 required fields. Notification sent to the administration . Once the administration update the request to received , user and administration can start the chat. If the deal is complete the administration can change the status to accepted. Once the request it complete the administration can change the status to complete . The user will have the call option to call directly from his mobile no. To the predefined admin call number. Call will be initiated from his mobile no.