how can I add a qualified timestamp to my PDF on the go (via iPhone)?
What do you mean by "qualified", exactly?
Contact that company and ask them how to implement it for PDF files. They probably have some kind of DRM-backed certificate that allows a document to be certified in a secure way. You'll probably need to pay for it, though.
I was told by Adobe to contact the forum 😉
They're just passing the buck... You can use a certificate to do it, but if it needs to be a specific one then you need to get it from the company that issues it.
I use a qualified signature but it does not contain a Timestamp per se - you need to implement it somehow - I know how to do it with sign live cc but not how to do it on the go....
Digital signatures contain the current time by default. However, it's not certified in any way, as it's just the current system time and can be set to anything before applying it. A certificate might have a web-server support that makes sure the timestamp is correct, but it's not something you can do yourself. Either it exists or it doesn't.
This is exactly the issue! But is there a Timestamp portal that provides such a Time Stamp from the Server side via the Web - I have not found one yet...