If your threshold of sales is either approaching or exceeding "X" for your country, regardless of how your sales are brokered, I would highly recommend you hire yourself an accountant and have them figure this out.
I've spent most of my software career as an independent "self-employed" contractor and having a regular accountant I can refer to for questions like this has more than paid for itself. The last thing you want is the Government coming back to you a year or two down the road telling you, you owe them money (with penalties).
We don't have VAT here in Canada, but we do have a Goods and Services Tax GST . And for years my main customers were in the US. Was I supposed to be charging them GST on my consulting/programming "software" services? My accountant did the digging, talked to the Revenue agency and got a ruling based on several different interpretations.
Maybe VAT is a lot more straight forward than our GST, but in my case the answer did depend on factors like my industry (software development) and whether said "tangible" product was being exported back into Canada. Well, I was building intranet systems used by employees of a Global company with offices in 70+ countries, so some aspect was being utilized in Canada. There was no simple answer.
Regardless of what you may read online, your tax collector will have the final say. Make sure you (and your accountant) know the facts for your circumstances.
I hope that helps.