I worked on the project on mornings, evenings and weekends and it took about 1.5 months to complete the MVP. I focused on iOS app first and it was also the chance to learn SwiftUI for me.
I managed to implements custom algorithms that would take care of keeping items in the right order and tracking products I buy on a regular basis to show them as suggestions later.
I already could have started using the app myself then and preparing for release on App Store.