xls to apk conversion is not searched as actual file conversion but as a way to turn an Excel sheet (.xls or .xlsx) into a standalone app. This is often the case when users are interested in making simple apps based on extensive forms or calculators prepared with Excel.
This is more of a programming solution for Android and you do not have to seek just a file converter, but one of the tools designed for this purpose. Since turning files into apps is rather popular, there are many tools available for this, often including tutorials that can guide the user through the process.
To name one for xls to apk export, SpreadsheetConverter works for this purpose. It is a HTML5 based solution (Excel add-in) that can be used not only to convert Excel spreadsheets to calculating web pages, but also to compile any Excel spreadsheet into a web app.
Updated: February 22, 2024