Bachelor thesis: eID IO - Applicatie besturing

My assignment was to continue working on the existing backend code and card reader software. The objective was to ensure that a company or private residence door or gate can be opened via an iOS and/or Android device. Additionally, a notification must be sent to the linked mobile devices of the customer to whom the card reader belongs when a bell signal is received at a card reader. Since it concerns access control, everything related to the assignment must also be done securely without compromising the stability and speed of the system. For this assignment, I need to continue working on an existing (C++) program for the card reader placed at an access point and the online panel where customers can see who entered and at what time. I have to write an application that works for both iOS and Android devices.