Build an Quiz-App for Android (Must be written in Flutter) -- 2

I need a Quiz-App for Android. The Quiz-App has the following requirements: * must be written in Flutter * Views ** First-Page which includes 3 Buttons (Play, Settings, Coins) ** Overview Levels - The user should see which levels are completed and which ones are not completed ** Overview Questions (Child-Object of Level) - The user should see which question are completed, not completed or right answered ** Question (Question, image or audio or nothing, answer(could be text or multiple choice)) Logic: * After every question which is answered right, then the user get 1 coin * The user has the opportunity to get 1 additional coin if he sees an ad. He could ado this in the coin view or if he answered a question wrong and do not have any coins. * The levels and questions are store in the app source as json. As follows the json structure. { levels: [ { name: "Level 1", questions: [ { question: "How high is the pentagon?", question_type: "text", answer_type: "multiple-choice", choices: [ "45 meters", "60 meters", "18 meters" ], answer: "45 meters" }, { question: "How high is the pentagon?", question_type: "image", path: "/path/to/image/in/source/code", answer_type: "text", answer: "45 meters" }, { question: "How high is the pentagon?", question_type: "audio", path: "/path/to/audio/in/source/code", answer_type: "multiple-choice", choices: [ "45 meters", "60 meters", "18 meters" ], answer: "45 meters" } ] } ] } * Its possible to add n levels and to each level n questions * Its possible to add image or an audio to a question. For example which animal sounds like .... therefore an audio file .... and which animal is on the following picture .... therefore an image file * If the user closes the app then the state must be saved. (How many coins he has and which levels and questions are completed). * The App should be localized, this means the app should be written in english, but the possibility is given to add more languages just be create a file which includes the labels for the additional language. * The App should look modern and should be usable on mobile and tablet. * Please create before you write the app some mockups, so that we can discuss before programming the styles and the ui. Thank you very much for your offer. If you need more informations, then please contact me! Thanks in advance. Complete design is uploaded with an explanation in the Quiz-App-Specification.md.