Hello,
I have over 7 years experience in reporting.
I would do a web application in Microsoft ASP.NET with SQL server backend. I would use custom reporting controls, so you can get charts, export capabilities (html, pdf, xls, xlsx...), and also, once hosted (on windows machine in your network, or on some server), you can access it from any device (pc, phone tablet...).
If you have any question, please let me know.
Thanks!