I need to watch many wallet addresses for new bitcoin transactions as they enter new blocks. I also need this transaction data to make updates on my end
What are my options?
Here are a couple strategies I've used:
Run a bitcoin node: bitcoind has a -blocknotify
flag you can run that will allow you to execute a command with each new block. You can then use JSON-RPC to query your node for all transactions/addresses in the block. It will take a bit of work to set this up, but it will work
Use a service: I've used https://www.blockcypher.com/ which works well, but it can be pricey. https://blockchainwebhooks.com is much more affordable, but not as many features.
Hope this helps! Let me know if you have any questions
If you want an android app to watch the balance of addresses, you can use Sentinal. It's created by the Samourai wallet guys, it's awesome.