Ask HN: How to convince customers that your app is serius business

I built an android application for a niche industry, which is much better than the existing solutions. Earlier they were using expensive desktop software and no cloud data backups. For this desktop software, company had salesmen/technicians on the ground for sale and maintenance.

I have been running a pilot with few customers I know and fixed most of the minor issues and all are happy with the product. I was planning for a fremium model with a nominal price(compared to the existing desktop solutions price). Now when I go to other customers, they don't seem to take this application seriously because they can download the application freely and I think the price is too low(which I am working on). As a solo developer, how can I convince the customers that this is a serious application?.

Note: This is in India. Most of the customers are not very tech savvy. For payments I will have to try some offline channels.