Dropbox Transfer follows the same encryption protocols as the rest of Dropbox. While at rest, all Dropbox files are encrypted, but end to end encryption would severely limit the functionality of heavily used features like previews and search.
We're always looking to improve and certainly open to suggestions (we have a feedback form on the Transfer page just for these kind of suggestions that the Transfer team actively monitors!).
This is something we started providing recently (based on user feedback we heard, like yours). There's now a "let me know when someone downloads" checkbox when you're making a Transfer (both on Desktop & web)
Right, this is a really good question. Dropbox Transfer achieves the same purpose as WeTransfer with a few differentiators. Unpacking this a bit, there are two parts here:
1) For a company with an established sharing model (shared folder, live-updating links), a departure or addition to this needs to be thoughtfully orchestrated. Moving to snapshotting content, gathering content inside and outside your Dropbox, and enforcing expiration in this tool is a very different paradigm.
2) However, specifically because we are also a storage provider, we can provide a much faster sending experience for them as we can remove the upload step, which is especially important for folks sending really large files. We have a large user base storing their content in Dropbox, this is a net new added value/functionality for them.
The most technically challenging part was probably wiring the storage & sharing side up to not behave like a traditional Dropbox shared folder or shared link (e.g. not take up storage quota or sync down to your machine). There were certainly a long tail of internal reliability work to get that operating smoothly (there are many internal services to work with here).
In terms of tricks at handling failures:
The first (and probably most important) thing is finding the failures. Bug bashing sessions and also just reading failure logs can help catch the trickier transient problems our integration or unit tests do not catch.
In terms of mitigating them, retries and correct error handlers in code are essential (e.g. Promise.catch case should not be ignored!). Retries on the client side are made a bit easier as we chunk uploads into 4mb blocks so any upload errors of actual content can be retried piecemeal.
Hi! Sending groups of files was definitely one of the focus areas here so hope Transfer can be helpful in this role.
Re: Tracking content, we actually do provide this in Transfer. If you specify a set of email recipients, rather than copying a shared link, we provide a few tracking features for you.
1) Record who has viewed or downloaded your content.
2) Remind your recipient if the content you sent is about to expire.
3) (Optionally) notify you to let you know when your recipient has downloaded your content.