I'm pretty sure that video feed is actually sent to your phone through a Dropcam cloud server. Your Dropcam is a client which connects to the cloud server, as is your phone.

Arguably that's the exact same architecture Helm are describing. The EC2 instance your Helm box VPNs into is (arguably) "the server" - in that it's the "public service" endpoint. A good lawyer could eloquently argue that the Helm device on your residential internet connection is no more "running as a server" than the Dropbox or Google Drive apps on your laptop or phone...

(Note: I've been doing a similar home-rolled version of this, where I have a mail server under my couch that opens a reverse ssh tunnel and forwards port 25 and 465 from whichever transient EC2/Azure/DigitalOcean/Hertzner/CloudAtCost VPS Ive got listed as my MX records. A little bit of Route53 API automation, some Ansible to set up the ssh tunnelling, and some "canary" gmail and live.com email addresses to check outbound deliverability when I go to switch VPSs... It's been running pretty much untouched since 2014 or so...)

Ha, but that's "okay" because it's a big company. They never have problems with being used for spam - of course I'm being sarcastic.