Filtering

Bloomr will run scripts (see Scripting) every time something happens on the blockchain.

Filters allow you to tell when those scripts will run, based on a static yet flexible filtering system.

Why are filters useful ?

You could run a script with no filter at all, wich will be ran for ALL transactions on ALL blockchains, and perform all filtering in your script.

That said, keep in mind that you will pay for execution time when those scripts are ran... so building a good filter is the key to have cost-efficient operations.