Streamcardano vs HelloSign Comparison Table

Compliant with legal regulations and be accepted by courts Yes with QES
Signature visible in a document Yes M2 Yes
Storage of documents Yes Yes
Sharing of documents notifications No
Signing workflow Planned for M3 Yes
Document templates filling forms No
Open-source solution Yes No
Distributed Non-proprietary storage N/A

It is the most advanced solution that includes integration with Dropbox (and thus allows to store signed documents), visible signatures, signing workflow and document templates. So this solution exceeds AdaStamp functionality. However, it is a proprietary solution of one commercial vendor, not yet integrated with any blockchain (the vendor performs some research in this direction, but it is not yet integrated within the product).