Cryptolens.
Like most people, I began to dabble in cryptocurrency around 2017. I started out buying some ETH and then trading it for XRP when that was supposed to be the next big thing. At the time, it seemed most cost-effective way to purchase was to buy ETH on Coinbase, transfer that to Binance and then trade there.
Over time what I started to notice was that the payout indicator on both Binance and Coinbase were not entirely accurate. The trade value back to a fiat currency was fine but it didn't account for the additional processing fees, transfer costs etc so you would actually end up with less than you expected.
The purpose of Cryptolens was to take this specific Coinbase->Binance->Coinbase pipeline and accurately indicate the true amount of fiat currency invested and paid out, accounting for all fees in the process.
The website uses Firebase as a database to store user account and portfolio information. It makes use of the RTD feature so that any changes made on one device are automatically and instantly reflected on any other device.
The front end uses KnockoutJS as a framework and bootstrap to help with the layout and design.
For tracking prices, a javascript library was created which has the concept of a tracked asset (any currency) and a gateway. A gateway is the exchange where a trade or purchase will happen and it holds the information about transaction fees. Gateways were created for Coinbase and Binance but the concept is generic so any exchange could be implemented in the future.
The long term goal for this project was to attract users who could use it to track the performance of their portfolio and then monetise it by using notified referral links to Coinbase, so that Coinbase would pay out a small commission each time a user made a purchase.
It was difficult to attract users as Cryptolens was not a full exchange, it was only an investment tracker. Ultimately given the difficulty acquiring users and the collapse of cryptocurrency prices in early 2018 the project ceased to be viable.