I wrote an open source crypto tracking app, Coin Stacks, which has some cool features I'd like to show off.
For a long time I've felt, and heard from the community "why should I trust my data with you" when it comes to all these portfolio tracking apps. My solution to that problem, for myself, and everyone else was to simply not host any servers, and make it open source.
https://play.google.com/store/apps/details?id=com.nebulights...
https://github.com/babramovitch/CoinStacks
The app works by calling out directly from the app to the exchanges a user wants information from, including any balances they have on them if you add your API keys.
For Watch Addresses it connects directly to various public block explores. It lets you know which one you're connecting to before you submit the address.
With the combination of watch addresses and exchange balances, you can get automatic balance updating without having to constantly change how many coins you own manually.
It was quite an interesting technical problem to solve, potentially dealing with dozens of different APIs, but I think I set things up in an easy to scale way where I can continue adding new exchanges and block explorers with minimal effort on my end.
All the API's share a similar interface that normalizes all the data between them, so I only have 1 network call per type of call (price, exchange balance, explorer balance) and some simple configurations for each exchange/explorer.
Technically speaking - The app contains 19 unique end points, and currently its possible for the app to be handling 53 simultaneous queries to exchanges for prices or balances, in addition to any watch addresses you add with the explorers. A lot can be going on, but doing it this way, prevents me from collecting crypto info.
I'm really excited to finally get this big update out there and see what everyone thinks! Feedback would be greatly appreciated!