Creating an overview of monthly expenditures and the remaining balance left of the account

We are looking for developers who can create a simple, yet sleek app: The idea behind the app is, that students have a limited amount of money to spend per month, and often they do not know where the money actually went to at the end of the month and how much they have left to spend. The app should consist of 4 screens: 1. Welcome screen with the name of the app: myWallet 2. A second screen should allow the user to enter his monthly budget (e.g. 100 Euros) and select the relevant month for which the budget applies. 3. A third screen should show a line with the remaining balance for the user. Below or above that line should be fields for the user to enter the name of an item he bought (e.g. Groceries) and next to it, there should be a field where he can enter the price he paid for that particular item. The sum of all the items the user entered should be deducted from the budget in screen 2, and be reflected in the remaining balance field on this screen. 4. The fourth screen will collect the total expenditures that the user had during a month (from screen 3) and enter these into the relevant monthly fields, so that he has an overview of how much he has spent each month. The app should know when a new month starts and ends and then transfer the expenditures to screen 4. Some pictures are attached to this description. They do not reflect the design of the app. They should only function as a visual description.