(AI-Powered) Web + Mobile Tax and Accounting App Development

I am considering developing a website and mobile tax and accounting application (if possible powered by artificial intelligence). I want the application to be professional and of high quality. The app should allow users to easily manage their own individual or company accounting tasks. I have a clear idea of the design of the app, but I am not sure how to implement it, so I want to work with reliable, referenced, and expert individuals in this field.

Mobile app is my priority, but the web version could also be considered. I am unsure which platform would be more advantageous and am open to suggestions.

I intend to initially make the system available for paid access. If there are individuals knowledgeable about accounting for sole proprietorships in Belgium, it would be easier for me to discuss how we can bring this to life with them.

The websites listed below make this possible, and they also have mobile applications. You can download and try them yourself:
-https://dexxter.be/
-https://www.astro.tax/
-https://www.accountable.eu/
-https://www.exact.com/benl/login