Build me an Android and iOS App

The project entails building a quiz app in both android and ios. The app will have the capability to present the user (1) 10 to 20 questions at random. (2) There will be only one database and it will include several categories of questions, such as, Easy, Intermediate, and Advanced. The user will choose the difficulty level of the quiz each time he takes the quiz. (3) There will be 10+ question types, such as: Multiple Choice Questions (MCQ); Multiple Choice Answers(MCA); Fill-in-the-Blanks (FIB); Short Answer (SA) which will provide a text input space; Ordering/Sequencing (ORD) in which items are arranged in the correct order, like the correct positioning of words in a sentence and historical dates etc.; Matching (MAT) where items in the right column are matched against items in the left column; Correct the Sentence (CS) in which the incorrect sentence (question) is edited and corrected in the text box provided; True/False (T/F) questions where the user puts a check mark on either true or false; Multiple Choice Text (MCT) where the user chooses one word or text from a dropdown list to enter into multiple blanks in a sentence; Word Bank (WB) in which the user drags one word from several given words for blanks in a sentence; Cloze (Cloze) where certain words have been taken out from a sentence, and the user has to fill in those empty text boxes. The backend should enable me to add/edit/delete questions from a single UI. It will also enable me to bulk upload questions in a csv or excel file, compatible with the above-mentioned characteristics. Each question should also have a space for explanation or instructions, which may vary from question to question. In addition there will be 4 or 5 pages such as the landing page and About Us page, etc. I need both versions, and I will provide the content, and I need the interface first to upload questions so as to test that everything is working fine. This will help both the developer and me, and save time.