Hopefully, for the last time and avoiding replies which involve misdirection and obfuscation. I have used a VPN where I am the host and “when inside my LAN“ CAN view live surveillance camera video feed using an iPhone and web access via IP address. There is no problem using NordVPN + Meshnet, or OpenVPN on my router. The camera website can be entered using a web browser and the cameras IP address. So once again, there is NO PROBLEM in doing this.
The problem only arises when the cell phone is used OUTSIDE of the LAN. Any form of acceptable solution must use VPN and not use port forwarding (I AGREE, I AGREE). My surveillance camera manufacturer happens to be Reolink and, whilst I am able to achieve web access to the cameras IP address the received live video feed cannot be decoded as it uses Adobe Flash Video (FLV) format. Reolink technical agree that without a web browser that supports FLV (and no major browser will support it as the plug-in iitself is extremely vulnerable to hacking) the REMOTE LIVE video cannot be viewed.
I had hoped that someone would provide a simple direct example, giving actual components used, eg OpenVPN on router (which one) using a defined surveillance camera, cell phone, host pc, web browser, etc, etc, where they ACTUALLY ACHIEVE remote live video viewing and not “I’m sure this would work if you tried it”. If you can’t provide these simple details then don’t waste time replying.
As others have mentioned, if you can't view your live camera feed while via a remote VPN connection that is hosted on your local network, then either you have set it up wrong, your cameras are preventing it (I wouldn't be surprised to find out that Reolink won't work over VPN, but I don't use that brand myself so I can't test that theory), or the "upload" speed of your home's internet connection is too slow to support video feeds..
You asked for specific information so he is my set up. I use OpenVPN which is hosted on my pfSense Firewall appliance (a "DIY" solution that cost me about $150 for the hardware used). While I use pfSense, OpenVPN is available on nearly every residential grade router sold in the last decade, so don't get hung up on my "hardware" choices. I use a Dynamic DNS service so that I have a unique and non-changing public URL that I use in my config files in leu of my actual public IP address that is assigned by my internet service provider. I have a service set up on my pfSense firewall that communicates any changes in my actual public IP address to this Dynamic DNS service. (Again most consumer grade routers sold in the last decade have the ability to communicate with the more popular Dynamic DNS services available). That service will forward any traffic from the non-changing public URL to my actual public IP address so I never loose access to my network even if my public ip address changes. I run IP cameras from a variety of manufactures (but mostly Dahua) and I run
BlueIris as my "NVR" software.
I can connect to the BI system either using the BI mobile app (a paid app) or by using the BI internet browser interface (free access). Both viewing methods work just fine over the VPN and both allow me to see live camera feeds as well as view saved footage and alerts. I can access these feeds using ANY device (mobile phones, tablets, computers, etc) that I have set up to use the VPN connection (which is a one-time setup of downloading the encryption key to the device while I'm at home and pointing the VPN to the right Dynamic DNS public url along with the correct settings for my connection).
Not only can I access my BI feeds over the VPN service, I can access anything else on my network as well (at least anything else that I want to be accessed over the VPN - I can limit access should I want/need to) . For example, I use a computer based DVR system to record TV and I can view live TV or recordings over the VPN without any issues too. I can also access my home automation system and control everything such as HVAC, lighting, A/V systems, home alarm system, or even close the garage door if it's left open all from my home automation app (or web interface).
EDIT - I remember that I actually did have an old Reolink RLC-410 camera in my system at one time and I could view it just fine over the VPN connection.