Another resurrected thread. I'm trying not to repeat myself within threads but every time I search to ensure I'm not accidentally doing that, the forum returns the message "database error".
Denise, to answer your question, we wired a Canary into our van and use a Netgear AC791L to serve as the bridge between it and my iPhone. I need the Netgear for work purposes anyway, so investing in it was a no-brainer. I think the monthly fee is something like ten bucks (Verizon), so I don't worry about it.
Here's a pic of the system in use, this being screen-shotted from my phone.
The red arrow points toward our dog on the rear couch (the image resolution is better closer to the Canary, for facial recognition purposes).
This same image was used on a recent animal-related thread in which not everyone agreed that animals should be left unattended in vans. I routinely use this to monitor the van while our dog is left in it for short periods (during cool weather only, obviously).