Ecoinia is a finished application for crypto-enthusiasts. Its functions allow users to follow coins’ prices, create and monitor their crypto-portfolio and keep an eye on their mining hardware. It as an easy and inexpensive way to dive into crypto-world and become an owner of useful, fast-growing and extremely promising service.
Since you are a programmer, suppose you know that the features you offer are already present in many sites, which allow you to track your currencies without having to install an application.
Also, it is difficult to trust an anonymous application and therefore this is an additional hurdle for those who want to help you in marketing.
Some of them have website/Android/IOS and email services
In general, you need to set up a site that serves these services and then a free subscription and try to market the paid subscription. I wish you success.