@r0jaq
You didn't say what type of entity for your "small business", so I'm assuming you mean a self-employed business that files Schedule C, since you appear to be using Online Self-Employed Edition.
If you purchased a subscription to such a service that you use in your business, you can use "other miscellaneous expenses". That will have a place for you to enter a description and amount and will ultimately show on the Schedule C, Part V.
If, on the other hand, your business runs such a subscription web service, then you need to explain more about what you need to know. If that's your situation, are you referring to a principal business activity code, or what?
