I talked with Viofo support and they told me it can't live stream in that way. Not sure about Thinkware Q800.You can use Viofo A139 or Thinkware Q800 for that. In terms of IP cameras that are not dash cams and you use them in the summer they might burn out but if your car is well vented IP cams work fairly well. Especially the Eufy outdoor cam Pro and Wyze v3 will give you better low light sensitivity that any of the dash cams ive seen so far (including the A139 Pro champ) I have a similar setup but instead of the Harman Spark I am using an old phone of mine as a hotspot with a data only simcard from google. They both came for free for me. Google Fi gives you a free data only simcard for each unlimited line. For monitoring and streaming I use this app on my old phone: https://play.google.com/store/apps/details?id=com.unicordia.dc_free
Well, you misinterpret most of my message : Google Fi gives you a free data only simcard for each unlimited line. So, you buy an unlimited plan and you get Sim cards for 2 phones. And it has pretty good coverage. it works on ATT Tmobile and other networks . Did you hoped to get a free data plan for no reason ? Dash cams by themselves will not stream, you need the whole setup not just a dash cam. Good luckI talked with Viofo support and they told me it can't live stream in that way. Not sure about Thinkware Q800.
Checked Fi, it is good for 4-5 but Google Fi for 1 user plan is 50$, with att it is going to be 25$ for unlimited.