Convert and add watermark programmatically using .NET

I have a question concerning choosing right component for two specific functionalities which will be part of 2 different web applications.
For first application I need component which will convert different document formats into html.
Second web application should have capability to merge an watermark image into docx and pdf documents and convert them into docx /pdf (for download) and images (i.e. png) which would be viewed in gallery.
I have browsed through your product family and it seems that GroupDocs.Conversion should have capability to deliver all mentioned functionalities.
I would like to hear your opinion, is this the right choice or should I consider another product such as Aspose.pdf ?
As a remark, we already use Aspose.Words.
Another question, what is the current version of GroupDocs.Conversion?

@sntSwd,

Thank you for your inquiry.
In order to guide you about the right API, we need to know for which platform (.NET, Java, Cloud) you need GroupDocs.Conversion.
Please share your preferred platform and we shall guide you accordingly.

Hello, it’s for .NET.

@sntSwd,

Thanks for sharing the platform details.
Please note that GroupDocs.Conversion for .NET is a back-end, UI-agnostic API that can be integrated in any .NET application/project.

You can convert these supported document formats into html using the API. Please visit this article.

You can simply add image watermark in the converted document. Get further details on this feature here and this is an example implementation.
But as far as document (PDF) manipulation is concerned (e.g. adding or removing watermark before document conversion), you cannot do this. GroupDocs.Conversion for .NET only allows you to add watermark (text or image) while converting the document.
So, if you want document (PDF) manipulation before the conversion process then you can use Aspose.PDF for .NET and then eventually convert such document to Word, Image or Html. Hence, document manipulation and then conversion is easy using Aspose.PDF for .NET. You can raise queries regarding Aspose.PDF here.

Current version of GroupDocs.Conversion for .NET is 18.10.
You may find following resources helpful regarding GroupDocs.Conversion for .NET:

Another question, pls.
Can you please confirm that GroupDcos.Conversion component is completely thread-safe and that we can use it in web service scenarios with multiple concurrent users accessing the component in the same application domain and process?

@SwdS_User,

We answered this query here.